Originating on General Hospital, Lucy arrived in Port Charles in 1986 as mousy librarian. She was involved with Kevin O'Connor and she was an alibi in his murder case. After she was duped by him, she wrote a tell all book to make some money. The mousy Lucy was now gone forever. She had an affair with Bobbie Spencer's then-husband Jake Meyer and miscarried his child. After that, her Aunt Charlene managed to set her up with Tony Jones, whom she eventually married. After Tony, she married Alan Quartermaine wearing a red dress, thus angering the Quartermaines. While married to Alan, she had an affair with Scott Baldwin and became pregnant. She also miscarried that child. After her marriage to Alan, she ended up with Scott, but she ended up leaving for New York with Greg Bennett.

When she returned to town, Scott had fallen in love with Dominique Taub. Dominique was diagnosed with a fatal brain cancer and she saw a kinder, gentler Lucy and convinced Scott to let Lucy be the surrogate mother for their child. Lucy gave birth to the child, Serena, in a cabin during a blizzard. Soon after, Scott was forced to flee town after being pressured by the mob. Lucy took this very hard. She ended up meeting Damian Smith and she reverted to her scheming ways temporarily. She made a bet with Damian that he could not bed Bobbie, which eventually led to the beginning of the end of Tony and Bobbie's marriage. She met psychiatrist Kevin Collins during this time, and he helped her return to the considerate Lucy she had become under Dominique's influence.

On Port Charles, Lucy found love with Kevin but they faced many challenges in their relationship. Lucy used her fledgling psychic powers to meddle in the lives of others and often placed herself in danger. She remained in love with Kevin when she was briefly married to Rex Stanton in order to keep an eye on Serena. Lucy also stood by Kevin during his mental breakdown and afterwards the couple planned to marry. Despite the engagement ring she wore, Lucy was insecure about Kevin's friendship with Eve Lambert and she tampered with Eve's car. This caused Eve to have an accident while Serena was in the car with her. Serena lost her eye sight but regained it afterwards. Kevin was disgusted by Lucy's actions and called off the wedding when they were about to say their vows.

Around this time Lucy was trapped in a cabin with brisk Dr. Ellen Burgess, and a strong friendship began, lasting with ups and downs until Ellen vanished in 1999.

Eventually Lucy reconnected with Scott and they fell in love again after they were involved in a plane crash together. The couple married and the found a baby girl named Christina at the Nurses' Ball. Unbeknownst to them, Julie Devlin and Frank Scalon were the child's parents and a bitter custody fight ensued. Lucy reacted angrily to the visitation rights Julie and Frank had secured and the news that Scott had adopted Christina under his name although the child could not be adopted under hers. When Julie kidnapped Christina and fled town, Lucy irrationally blamed Scott, and ended their relationship. They divorced amicably and her place in Serena's life remained intact.

In time, Lucy and Kevin found their way back to one another when they worked together sort out the machinations of Dr. Rachel Locke. They also uncovered the identity of Kevin's daughter Livvie and Lucy moved back in to the Lighthouse with Kevin.

The duo depended on each other more than ever at this time, with Livvie constantly in danger and enthralled by unknown forces, and the town under a dark cloud. As the months passed, Lucy pieced together the clues and discovered that Port Charles had a vampire. Kevin put aside his doubts and believed Lucy. Her theory was correct and a trip to Transylvania revealed that she was one of the last in a line of vampire slayers that dated back centuries. She also gained a cousin, Rafe Kovich. Rafe was actually an angel and he helped Lucy and Kevin determine that Caleb and Michael Morley were one in the same and a vampire.

Lucy, Kevin, and several others managed to vanquish Caleb, but only temporarily. He returned in weak state but slowly gained power by tapping into the fear and weakness in the town. Caleb planted thoughts in Lucy's head to make her think Kevin wanted to resume his relationship with Eve. With help from Rafe, Lucy escaped Caleb's duping but he used another tactic. He tried to convince Lucy that Christina was making contact with her. The misunderstandings between Kevin and Lucy continued, along with manipulations by Caleb and Lucy sought comfort in the arms of Eve's estranged husband Ian Thornhart and they had a one-night stand.

Kevin and Lucy patched up their differences once they believed Caleb was out of their lives but Lucy became suspicious of Kevin's meetings with a mysterious veiled woman. The issue resolved itself when Kevin threw a surprise wedding for Lucy, with Christina as a surprise guest. After nearly a decade, Lucy became Mrs. Kevin Collins. After the wedding, Lucy learned that Kevin's mystery friend was actually Christina's birth mother Julie. She had returned to town to give Christina to Lucy because Julie had a terminal illness. Lucy was overjoyed to be reunited with her adopted daughter and she promised that Christina would learn how much Julie loved her.

With her new family together in the lighthouse, Lucy had to contend with an old friend of Kevin's, Paige Smith. She showed up on their doorstep and moved in. Lucy was suspicious of Paige because she was supposed to be Kevin's age but she looked considerably younger. As Paige grew closer to Kevin, she asked him to paint her portrait and she claimed that her husband had been killed in a car accident. What Lucy and Kevin did not realize was that Paige was also killed in that accident and was back on Earth only to resolve her relationship with Kevin. Paige got other ideas and plotted to replace Lucy in the lives of Kevin and Christina. Paige appeared in her angelic form when Kevin was electrocuted and nearly pulled him into death.

Lucy was already suspicious of Paige when she found Christina left alone when she had been left in Paige's care. Unbeknownst to Lucy, Paige had been beamed up to Heaven for a reprimand. Lucy was outraged and threw Paige out of the house when she returned. Kevin was similarly disenchanted and cut Paige out of his life, although he did agree to paint her portrait. Kevin finally managed to piece together Paige's true identity as an angel. Lucy walked in on him and Paige in a private moment and he told Lucy about Paige's real persona.

Paige explained that her few months on Earth were supposed to be spent exploring why she was returned to Earth. Lucy bought 3 plane tickets to London and took Kevin and Paige along. They visited Paige's family's mansion and placed her portrait on the wall. Only a portrait of ancestor Rebecca Barrington was missing. Paige realized she must be related to the Barringtons and after sharing a tearful goodbye with Kevin, she saved Alison Barrington's life and then vanished.

Lucy's peace of mind was shattered shortly after Paige disappeared. Kevin's former wife and Lucy's former rival, Eve Lambert, was killed in a car accident. Lucy had grown to become friendly with Eve and was devastated by the loss. She managed to help both Kevin and Eve's husband Ian come to terms with their grief.

The accidental discovery that Victor and Mary Collins were turned on by a scented candle that Alison had created prompted Lucy to help Alison develop a candle business. Her good idea hit a rough patch when her stepdaughter, Livvie, vehemently opposed this "witchcraft". Kevin took Livvie's side, opposing Lucy. Soon after, Kevin vanished after making contact with the spirit of Rebecca Barrington in the candle shop. Lucy lashed out when many assumed that Kevin was dead and she tried to help Alison after she was arrested for Kevin's murder. With the support of Ian, Victor, and others, she kept a rein on her emotions and tried to bring Kevin back. She got clues from the other side which she could tell were from Kevin. They led her to Rebecca's portrait, which had been slashed by Livvie. Lucy and Ian began repairing the portrait in hopes of bringing back her beloved "Doc". Kevin showed up in the "nowhere world" of Barnadoon with Rebecca. He tried to call out to Lucy and she vaguely heard him. Lucy and Ian channeled Kevin several times over the next few weeks. It worked, but each time left Ian more debilitated afterward. Lucy refused to continue to put Ian at risk because she cared for him too much to lose him as well.

Lucy eventually realized that if she and Alison could clear Rebecca's name, Rebecca would be able to rest in peace and Kevin would be able to return. Lucy, Alison, Ian, Kate, Jack and Jamal all worked on it they convinced a judge to overturn Rebecca's conviction. In Barnadoon, Rebecca faded away to heaven right before Kevin's eyes. Before vanishing completely, she told him that someone on Earth had to light a special candle for him to return. Back in Port Charles, Victor informed Lucy that "Kevin's" remains, which were really ashes from the urn of Kevin's twin brother Ryan, were found and Lucy lost all hope of finding her husband. Just then, a sketchpad appeared in front of Kevin and he drew a sketch of Lucy which included the date, and it floated down to her and restored her faith in him. Days later at the hospital chapel, Rafe pulled the magic candle out of his backpack and lit it. Kevin returned to Lucy and they shared a heartfelt reunion.

Once Kevin and Rafe were both back, Lucy turned her energy to helping Rafe recover from amnesia to realize that Alison, not Livvie, is his true love. This drove a wedge between Lucy and Kevin, since Kevin took his daughter Livvie's side and Lucy refused to back off. In time, she realized that Rafe sold his soul and would only gain it back by falling in love again with Alison, even though Livvie claimed she was pregnant with his child. Kevin eventually agreed with Lucy when he admitted that Livvie was acting very odd and he decided to check her medical records. He noticed some of her files were missing. A lab assistant confessed that Livvie had blackmailed her into changing the paternity test results of her unborn child. Kevin shared the news with Lucy and prepared to confront Livvie over her child's paternity. When he entered Livvie's apartment however, she mistook him for Frank, her unborn child's father, and injected him with a psychotropic drug.

Kevin assumed the personality of his dead twin Ryan and seduced Lucy. Afterward he tried to kill her. He also tried to hurt Alison which prompted Lucy to have him committed to a psychiatric care center. It was also revealed that a young prostitute on Jasmine Island, the place where Kevin retreated to after being injected, was murdered.

In dealing with her pain, Lucy grew closer to Ian. He was still dealing with the pain of losing Eve, while Kevin seemed to get worse instead of better. He was particularly agitated by the growing connection between his wife and Ian. It became increasingly clear that Kevin would not be returning to his normal self and Lucy and Ian admitted they were falling in love.

About the same time, the band The Stephen Clay Experience visited the town. They released a song that everybody except for Lucy and Rafe seemed mesmerized by. When Stephen Clay was revealed, he looked exactly like Caleb. This caused Rafe and Lucy to go into slayer mode to protect the town from the vampire. Elizabeth Barrington was also turned into a vampire and she turned Ian. Lucy comforted him, and the two realized that her slayer powers lessened his need to feed when they made love.

Lucy, Rafe, Alison and Ian devised a plan to rid the town of vampires. They planned submerge vampires that have fed in a healing spring that would return them to their human selves. The group planned to toss all the vampires in. Unfortunately, the plan did not go off as well as hoped because Joshua tried to blow the spring up and people were injured. Lucy also fell into the water.

Since Ian had not fed, he was unable to be healed. After the explosion, Lucy did not feel well. She was anemic, tired and her hair started falling out. Ian discovered that she had a disorder in which her own blood was poisoning her. Lucy also realized that she had lost her slayer powers. Lucy was not deterred and she remained determined to save Port Charles from Joshua and his vampire clan and to convince Ian to believe in the goodness inside of him. Lucy helped Ian accept his status as a vampire after Christina went missing after she wandered off and was lost in the woods. Ian sensed the danger and located Christina just as she lost her footing and went over a ravine. Ian used his powers to dive over the edge and rescued her. Lucy pointed out to Ian that he had only been able to save her because of the powers he possessed as a vampire. She encouraged him to view who he was, a vampire with a heart, as a gift.

In 2004, Lucy made an appearance on General Hospital when she returned to the Quartermaine home with Kevin to attend the memorial service for Lila Quartermaine. She honored her connection to the Quartermaine family by wearing a red dress similar to the one she wore when she married Alan Quartermaine. She spoke fondly of Lila and referred to her one last time as "Mother Quartermaine."