Little is known about Damian Spinelli prior to his life as a college student at Port Charles University. His grandmother raised him in Oakfield, Tennessee.

Damian Spinelli was a student at PCU when Lorenzo Alcazar hired him for his expert computer skills. Lorenzo paid him to create a flash drive with false incriminating evidence against Sonny and Jason. Later, Ric Lansing used the "missing" flash drive to frame Sam McCall in the hopes of forcing Jason to make a mistake. Jason didn't. Instead, Jason started following the clues and eventually figured out that Spinelli was the key to exposing Ric's corruption and his association with Lorenzo. However, the false evidence implicated Sam.

Spinelli was completely unprepared for the situation he found himself in. A self-professed computer geek, Spinelli's strength was his mind, not his brawn.

Jason and his girlfriend, Sam, took Spinelli to a safe house but, during an attack by Lorenzo's hit-men, he disappeared. He reappeared and met Lulu Spencer. Lorenzo had kidnapped both, but Spinelli escaped once again. Lulu and Jason tracked him down to his grandmother's home in Tennessee.

Eventually, Spinelli was able to debunk the information on the flash drive, which exonerated Sam. Because Jason rescued Spinelli several times from Lorenzo's henchmen, Spinelli's vowed his eternal gratitude and undying loyalty.

Initially, Jason tolerated the strange young man. He comprehended very little of what Spinelli said because Spinelli had a unique way of saying things, but eventually they grew to be close friends. It was Spinelli who became one of Jason's few confidants when Jason learned that the baby that Elizabeth Webber carried was Jason's. Spinelli urged Jason to step forward, convinced that Jason would be a wonderful father. Jason was reluctant because his career choice as a mob enforcer endangered his son. Spinelli disagreed, but he supported his friend's decision. As time passed, Jason took Spinelli under his wing. He gave Spinelli a job as his computer expert and invited Spinelli to move into the penthouse.

Spinelli partnered with Dillon Quartermaine and Lulu to find out who had killed Lulu's grandfather, Rick Webber, years before. Previously, everyone had believed it had been Lulu's mother, Laura, but just before she went back into a catatonic state, she asked Lulu to prove it was Scott Baldwin who had killed Rick. After Alan Quartermaine died, Spinelli, Lulu, and Dillon found a letter from Alan that was addressed to Luke. In it, Alan admitted that Scotty had accidentally killed Rick when he thought Rick had murdered his ex-mistress and was trying to drug Laura. However, it was Laura who had accidentally killed the woman.

As Spinelli spent time with Lulu, he developed a crush on her. His crush was revealed when Spinelli worked with Jason to rescue Lulu and the other hostages from the Metro Court Hotel after it had been taken over by Jerry Jacks. Lulu made it out safely but she did not return Spinelli's romantic feelings. Shortly after, Jason discovered that Georgie Jones had a crush on Spinelli and told him. Spinelli was overjoyed, but confused.

Tragically, he discovered Georgie's dead body in the park in December of 2007. She was a victim of the Text Message Killer. Spinelli felt guilty because he had been unable to protect Georgie. The Port Charles Police Department named Spinelli a suspect in the murder. After Maxie Jones's boyfriend Cooper Barrett's apparent suicide, Georgie's sister Maxie grew to believe that he'd actually been murdered. She enlisted Spinelli in the hunt for Cooper's killer, assuming that it was the Text Message Killer. Spinelli and Maxie did not get along at all, arguing at every turn.

While searching for clues, Spinelli and Maxie became trapped in a storm drain and had to spend the night. It was during this escapade that Maxie began to soften in her attitude toward him. Lulu began to suspect Logan Hayes was the serial killer. During a stakeout at Logan's apartment, Maxie kissed Spinelli to avoid the suspicion of a cop. It was at that point that Spinelli began to fall for her. Eventually, it was discovered that Diego Alcazar, presumed dead, was the killer. During a confrontation between him, Spinelli, and Maxie, Diego fell to his death.

Maxie and Spinelli worked together once again after Sonny's son Michael was shot in head after a bullet meant for Sonny ricocheted. They discovered that Ian Devlin was the culprit. In another fateful confrontation, Jason saved Spinelli and Maxie by shooting Devlin to death. Spinelli admitted to Jason that he'd fallen in love with Maxie. He also sought relationship advice from Diane Miller, Sam, and Jasper "Jax" Jacks. At that point, Spinelli began to woo Maxie.

Spinelli grew closer to Maxie after he helped cover up the accidental death of Logan at Lulu's hands. Soon thereafter, Johnny's deranged father, Anthony, kidnapped Maxie. She escaped and made her way to Spinelli. He promised to keep her safe. Out of appreciation, she made love to him but immediately regretted it, believing she used him for comfort sex.

The pair grew closer once again when Maxie joined Spinelli on a stakeout. Maxie was nearly hit by a car before Spinelli pushed her out of the way and was struck by the vehicle. Maxie rushed him to the hospital where Matt Drake operated on him to remove his ruptured spleen. After surgery, Spinelli developed an infection. Matt's brother, Patrick, successfully worked to save Spinelli. While Spinelli recovered at Jason's penthouse, Maxie cared for him.

Just as Spinelli grew closer to Maxie, Kate Howard, Maxie's boss, hired Johnny to accompany Maxie to highly publicized events that could be showcased in Crimson, Kate's magazine. The two flirted and Spinelli was extremely jealous of the time Maxie spent with Johnny. However Maxie had her turn to be jealous after Spinelli met a girl named Winifred Leeds. She was a huge fan of the online game he'd created, "Stone Cold Saga." Her computer prowess matched that of her idol, and the two became fast friends. Maxie warned Spinelli that Winifred was not to be trusted.

It became obvious that Winifred was falling for Spinelli, but he made it clear that his one love was Maxie. It was soon revealed that Winifred was an FBI agent, working to take down the Corinthos empire, and was using Spinelli to surreptitiously gather evidence against Sonny and Jason, as well as Spinelli. However, she began to develop true feelings for Spinelli. Feeling threatened, Maxie seduced Spinelli. When he realized that the sex had been merely an attempt to distract him from Winifred's charms, the two argued. Before Maxie had a chance to apologize, he was arrested for violations of the Homeland Security Act.

Spinelli was released on bail and was present at General Hospital when a deadly biotoxin was released at the hospital and a fire broke out. Spinelli and Winifred worked together to assist during the crisis after the hospital's wireless connection was lost. Spinelli became trapped in a utility closet. An explosion knocked him out, but Jason and Sam rescued him. Upon reaching safety outdoors, Spinelli and Maxie were reunited and kissed passionately.

The following day, Winifred's superior, Agent Rayner, threatened to arrest Spinelli unless he was provided with enough evidence against Sonny to put Sonny in prison. Winifred urged Spinelli to go on the run and, later, showed up on his flight to Los Angeles, surprising him.

While Spinelli was in L.A., Cassandra Prescott kidnapped him and ordered him to help her break into a gallery to steal a ten-million dollar painting. He got a coded message to Winifred, but it was Maxie who was able to decrypt it. The two women, with the aid of Jason and Sam, rescued Spinelli. Winifred took full credit for capturing Prescott, so that the rest would not be implicated.

Because of her exemplary work preventing the heist, Winifred was promoted. This allowed her access to the files that incriminated Spinelli. With her help, Spinelli was able to release a worm onto the FBI computer system, which destroyed all evidence against him. He and Sam worked together to destroy the physical evidence, enabling Spinelli to eliminate the threat of prison. Soon thereafter, Sam and Spinelli partnered to become Jackal and McCall Private Investigations.

Maxie's stepfather, Mac Scorpio, did not like Spinelli, mainly because of his involvement with the mob. He forbade Maxie from seeing Spinelli, so she moved into Lulu's apartment. In July of 2009, Spinelli sang a love song to Maxie at Jake's during karyoke night. His voice wasn't perfect but he sung from his heart, which won hers. They made love that night. The following morning, he proposed to a stunned Maxie. She refused to give an answer at first but later admitted that she wasn't ready for marriage. Spinelli courted Maxie the old-fashioned way, and the two, to Maxie's dismay, remained chaste.

Spinelli decided to again ask for Maxie's hand in marriage and planned an elaborate date. Maxie declined. Spinelli tried to win Maxie's hand in marriage one more time -- this time, at a family dinner with Mac, Maxie, Robin, Patrick, and Lulu. Mac became enraged and hurled epithets at Spinelli. Maxie, to defy her stepfather, agreed to marry Spinelli.

As their nuptials approached, Maxie worked to convince family and friends that she really wanted to marry Spinelli but admitted to Lulu that she'd made a mistake. Lulu urged her to call it off, but Maxie refused to break Spinelli's heart. Just before the rehearsal, Maxie told Jason that she feared she'd leave Spinelli at the altar and begged him to make sure she went through with the wedding. Spinelli overheard this.

During the ceremony, when it came time for him to recite his vows, Spinelli released Maxie from her obligation, stating that they should be wed only if it was what they both wanted. They both expressed their mutual gratitude and love and vowed to be the best non-husband and non-wife they could be to each other. Mac was very relieved. Friends and family celebrated the non-wedding at Jake's.

Kate Howard, Maxie's boss, arranged for Maxie to welcome well-known artist Franco before his art show. She agreed to pose for him. He blindfolded her and posed her lying on the ground inside of a chalk outline. When she realized what he'd done, she exploded, explaining that her sister had been murdered. He apologized. Soon, Franco's intensity lured Maxie, and the two slept together.

Spinelli sensed that Maxie might be feeling trapped in their relationship and arranged for the two of them to recreate the moment at which they had both begun to fall for each other -- the night they were stuck together in a storm drain. Again, they became trapped, for real, and spent the night until Johnny rescued them. During the event, they both developed hypothermia and ended up in the hospital.

Maxie developed pneumonia and, as a recipient of a heart transplant during childhood, she nearly died. Spinelli begged an unconscious Maxie to return to him. Between life and death, Maxie was reunited with Georgie, who said that Maxie had too much to live for and suggested she go back to her true love. Spinelli realized that he was constantly putting Maxie at risk. He considered breaking up with her, for her own safety, but she refused.

The non-marriage between Maxie and Spinelli continued to be tested after Spinelli was distraught over Jason's decision to place himself in prison to protect Carly's son Michael. Spinelli joined Carly in her quest to punish those she believed to be responsible for Michael's prison sentence. While Spinelli missed Jason, he and Maxie drifted apart and ended their relationship.

When Jason was released from Pentonville, Spinelli focused his efforts on helping his mentor and boss track down the elusive serial killer, Franco and an infamous mob kingpin, known as the Balkan, that was targeting Sonny's past love, Brenda Barrett.

When Brenda arrived in Port Charles, Spinelli was smitten and dubbed her "The Divine One." That did not sit well with Spinelli's past love, Maxie Jones. Brenda sympathized with Spinelli over his love life and confided in him that she always hurt the men she loved. She then used her charms to dupe Spinelli into revealing the location of a Balkan trade that she thought she should be in on.

Carly and Brenda's enmity for each other could be traced back to their tangled love lives with both Sonny and Jax. Although Carly had since married Jax, Carly was upset that her ex-husband, Sonny, planned to marry Brenda. Once again, Carly enlisted Spinelli's help in digging up dirt on her rival. Spinelli was reluctant because he adored Brenda. He uncovered a past connection between Brenda and Sonny's son Dante but the information was not damning enough to stop Brenda's wedding to Sonny.

Right after the reception, the Balkan staged an explosion and kidnapped Brenda. It was Spinelli who discovered that the Balkan was hiding in plain sight, masquerading as Theo Hoffman, a lawyer in Diane Miller's firm. Spinelli's cyber sleuthing also led to the discovery that Brenda's confidant and friend, Suzanne, was the Balkan's wife. That discovery proved to be crucial in taking down the Balkan.

Spinelli overheard Diane Miller working on a novel and was impressed by her literary talent. They decided to write a book together, using cases from Spinelli's P.I. files. They titled it The Secret Life of Damian Spinelli. Spinelli told a very pleased Maxie that she was the inspiration for his book. Spinelli had many fantasies about being a gumshoe that ended up in print.

Spinelli stood by his friend and mentor after Jason's son Jake died after being hit by a car. Sam and Jason decided to move ahead with their plan to have a child and Spinelli was supportive of the idea. Spinelli rushed Sam to the hospital when she experienced stomach cramping on a stakeout. As Spinelli eagerly awaited Sam's pregnancy test results Lisa Niles took Robin, Patrick, Steve Webber, and Maxie hostage in a hospital conference room.

Spinelli was distraught when he learned Maxie was in danger. He leaped into action and climbed through a vent that ended in the conference room. He crashed through the ceiling and tried to secure Maxie's safe release. Lisa shot at Maxie but hit Spinelli instead when he jumped in front of the bullet meant for Maxie. Spinelli's gunshot to the chest required emergency surgery and Maxie's boyfriend Matt Hunter performed the operation. While Spinelli was unconscious, he imagined he was a gumshoe from decades past and when he awoke he had a new persona. He spoke as if he were an old-fashioned gumshoe and referred to Maxie as a "dame' and called Diane "cookie." Spinelli referred to himself as "Jackal P.I." He recognized everyone and his memories were intact but he no longer possessed his super computer skills.

As Jackal P.I., Spinelli enraged Sonny when he took twenty million dollars from him and warned him he was cracking down on organized crime in the city. Maxie intervened and protected him from Sonny's wrath. Jackal P.I. went after Anthony Zacchara next and confronted him with a gun. Maxie informed Jason of Jackal's plans for Anthony and Jason hired Jackal to watch a bakery for evidence it was a front for drug smuggling. Jackal was unaware that Jason had made up the job to keep him out of trouble. Jackal P.I. immersed himself in his stakeout of the bakery and he discovered there was something mysterious going on Maxie continued to feel responsible for Spinelli's Jackal P.I. persona and she continually tried to jog his memory. Jackal P.I. did not respond to Maxie's advances and she was annoyed when he developed a crush on Lulu. The persona of Jackal P.I. started to lose hold over Spinelli when Maxie took him to Georgie's grave. He told Maxie she needed to stay away because he could not care about anyone because he would only lose them. Maxie agreed to give him space.

Maxie made another attempt to bring back Spinelli while Jason was hospitalized after he experienced head trauma from a car accident Maxie claimed Jason asked Spinelli to be his best man when he married Sam and convinced him to visit Jason. As Jackal P.I. struggled to remain composed in the presence of his friend, Spinelli broke through and begged his mentor to survive.

Spinelli was relieved when Jason was released from the hospital and was able to marry Sam. While the newlyweds were gone on their honeymoon, Spinelli revealed to Maxie that his cyber skills had disappeared but he found a way to access information using a network called Friends of Spinelli, or FOS. He contacted his network whenever he needed information he could retrieve on his own. He used FOS when Franco left graffiti tags around Port Charles shortly after Sam and Jason returned from their honeymoon. His connections deciphered the tags as having a message related to creation and they also found Franco's location so Jason could kill him. As Sam and Jason settled into married life the time came for Spinelli to find a new place to live. He had decided to pursue Maxie again despite her relationship with Matt and he moved in as her roommate. Maxie remained committed to Matt even though she questioned Matt's interest in Elizabeth Webber. Maxie asked Spinelli to help her make Matt jealous by spending time with her and he agreed.

Spinelli hoped to win Maxie's heart once again but his pursuit of her was sidetracked when Jason was hospitalized after he suffered another health crisis. Jason and Sam told Spinelli that they were expecting a child and that posthumously Franco had sent them video footage of Jason as an infant. Jason asked Spinelli to look into the authenticity of the footage.

Eventually Jason made a full recovery but his recovery was bittersweet as Doctor Robin Scorpio-Drake died in a lab explosion after creating the drug protocol that saved Jason's life. Spinelli broke the news to Maxie that her beloved cousin had died and he promised to remain by her side while she grieved. Spinelli had concerns about how Maxie handled the loss especially after she claimed she would not attend Robin's funeral. She did eventually attend and announced that she had killed Robin.

Spinelli believed that Maxie was in shock due to her grief and he and Maxie's friends and family explained that although her purse strap caught on a gas line, Robin's death was an accident and not her fault. Maxie refused to accept that reasoning and was angered when her father refused to arrest her for killing Robin. She then confessed to the murder of Lisa Niles and Mac was forced to take her into police custody.

Maxie also confessed to the murder of Officer Briggs and claimed she had framed her to take the fall for Lisa's death. Maxie was officially charged with the crimes although Spinelli maintained Maxie's innocence and he begged her to recant her confession. Maxie refused but Spinelli was determined to find the real killer. He reenacted the night of Lisa's death and realized that Matt killed Lisa in an intoxicated state but had not remembered what he had done.

Spinelli brought his idea to Maxie and she confirmed that Matt had in fact killed Lisa but did not remember doing so. She begged Spinelli to let her take the fall for Matt so he could be there for Patrick and Emma in Robin's absence. She explained that she had already taken Robin from them and she refused to take Matt away from them as well. Spinelli agreed although it pained him to see Maxie sentenced to twenty years in prison without parole. As Maxie was taken away he vowed to clear her name.

Spinelli uncovered video surveillance footage that showed a man issuing the blow to Lisa's head that led to her death. Spinelli knew Maxie wanted to protect Matt so he altered the footage to ensure that the man could not be clearly identified. The judge refused to release Maxie based solely on the footage unless she revealed who had killed Lisa. Eventually Maxie signed the document that would restore her freedom in exchange for the killer's name and told Matt that he had been the one to kill Lisa. Maxie was angered over the predicament and focused her anger on Spinelli.

When Maxie's day in court arrived, she and Matt used a brief recess to marry one another so Maxie would be unable to testify against Matt. Spinelli was devastated by Maxie's decision and tried to remind her of the reasons why she swore she would never get married. His pleas fell on deaf ears and Matt and Maxie left the courtroom to begin their lives together. Shortly after the wedding, Matt remembered killing Lisa and turned himself in. He was sentenced to prison and started serving his time immediately.

In Matt's absence, Spinelli hoped that Maxie would forgive him so they could resume their friendship. Instead, Maxie remained angry at him and refused to share an apartment with him any longer. She instructed Spinelli to delete her contact information because they were no longer friends. Spinelli responded by telling Maxie that he was done showing her kindness and patience because she had never shown those to him. After Spinelli removed Maxie from his life, he focused on his work as a private investigator. Specifically, he worked on an investigation of Heather Webber.

Spinelli shared what he learned about Heather with Jason and the police department. His findings played an important role in identifying Heather's crimes, one of which included making Sam believe that her son was dead by switching her healthy son with a deceased newborn. Spinelli helped Jason put the pieces together to track down Sam's child and as part of finding the child he met a lab technician named Ellie Trout. Ellie and Spinelli started dating and their relationship became intimate but it soon hit a snag after Maxie filed for a divorce and declared her love for Spinelli. He was torn between the women but decided to move forward with Ellie.

As Spinelli's new romance blossomed, Jason was killed after he reunited Sam with her son. Ellie helped Spinelli grieve and they grew closer until Ellie became Maxie's roommate. Spinelli had failed to disclose that he and Maxie had once been more than friends and Ellie was hurt by the news. Meanwhile, Maxie chose to get over Spinelli by carrying a child for Lulu and Dante. Spinelli was in awe of Maxie's decision and Ellie accused him of putting Maxie first and ended their relationship. Spinelli hoped that he and Ellie could reconcile their differences and asked her to meet him on the hospital rooftop on New Year's Eve. When Ellie did not show, Spinelli slept with Maxie while he was intoxicated, unaware that Ellie had been in a car accident on her way to meet him.

When Spinelli learned that Ellie wanted him back, he immediately regretted his night with Maxie and was grateful when Ellie forgave him. Their relationship seemed to be back on course until Spinelli revealed that he desired children whereas Ellie did not. They agreed to table the discussion and focus on the present although Spinelli was not pleased with Ellie's suspicions that Maxie was hiding something about her pregnancy.

After Maxie gave birth, Ellie confessed that she had discovered Maxie's secret. The child Maxie carried was the child that Maxie and Spinelli had created on New Year's Eve after Maxie miscarried Dante and Lulu's biological child. Spinelli was furious with Ellie and pushed her away as he processed the news. He fell in love with his daughter instantly but also witnessed the love Dante and Lulu had for the child as well. Spinelli confronted Maxie about her deception and she admitted that she loved their child but could not destroy Lulu and Dante by taking away the child they believed belonged to them.

Dante and Lulu named the baby Connie and they asked Maxie and Spinelli to be the godparents. At the ceremony, a lab technician interrupted and announced that Maxie and Spinelli were the biological parents of the child. After the truth came out, Spinelli and Maxie decided that they wanted to raise their daughter while Dante and Lulu petitioned the court for custody. A legal battle ensued and Lulu tried to declare Maxie to be unfit as a mother. The judge agreed with Lulu and awarded sole custody of Connie to Spinelli and barred Maxie from having any contact with the child. Ellie remained supportive of Spinelli throughout and apologized for her role in keeping him from his daughter. He forgave her and they resumed their relationship.

As Spinelli adjusted to parenthood, Ellie received a job offer in Portland, Oregon. They decided to leave Port Charles and Spinelli said heartfelt goodbye to Maxie. He admitted that a part of him would always love Maxie and he allowed her to hold their daughter. While Maxie bid her child farewell, Spinelli announced his plan to rename their daughter Georgie. Maxie was deeply moved by Spinelli's decision and they shared a kiss before Spinelli left to begin his life in Portland with Ellie and Georgie.

Several months later, Carly Jacks and her boyfriend Franco paid a surprise visit to Spinelli and Ellie in Portland. Carly and Franco were in need of Spinelli's technical support and during the visit Spinelli proudly introduced his daughter to Carly. He shared that he loved staying home with his daughter and hoped that one day soon Maxie could also be a part of Georgie's life. When Maxie was granted visitation, Spinelli welcomed her reunion with Georgie. He also met Maxie's new boyfriend Nathan West. Spinelli and Nathan agreed that Maxie was wonderful and Spinelli was pleased that Maxie and Nathan were together.

After Maxie's visit, Ellie questioned Spinelli's feelings for the mother of his child and instructed him to find out if he still wanted a life with Maxie. He arrived in Port Charles intent on a romantic reunion with Maxie even though she was involved with Nathan. Maxie was caught off-guard by Spinelli's appearance and she admitted that she was torn between both men. When Nathan learned of Maxie's conflicted feelings, he stepped aside and encouraged Maxie to be with the father of her child. However, Spinelli and Maxie each questioned if they had made the correct decision as they struggled to watch Nathan and Ellie together at the Nurses Ball. After the event, Spinelli and Maxie realized that what they had was in the past and Spinelli reunited with Ellie while Maxie and Nathan reconciled.