Private nurse Rosalie Martinez arrived in Port Charles with several secrets about her employer Nina Clay. She knew that although Nina had recently emerged from a lengthy coma, she did not require the use of a wheelchair and that she was wealthy. As Nina's sole confidant, Rosalie also knew that Nina was intent on seeking revenge against a long list of people that she believed had wronged her. The list included Nina's husband Silas, her husband's former mistress Ava Jerome, and Ava's adult daughter with Silas named Kiki. Nina assigned Rosalie the task of breaking apart Kiki's relationship with Michael Corinthos but she was unsuccessful in her attempt.

Rosalie helped Nina scheme and plot until Silas realized that Nina had faked her wheelchair dependency and that she had lied to him repeatedly. Although Rosalie was no longer employed by Nina, she was still forced to do her bidding because Nina held a secret that Rosalie did not want revealed. Rosalie knew that Nina planned to steal Ava's unborn child but she valued her own secret enough to share Ava's whereabouts. As she tried to come to terms with her decision, Rosalie ran into Michael. They had bonded a few weeks earlier when they were held at gunpoint by a thug whom Michael had later shot and killed. Michael and Rosalie used alcohol and each other to escape their troubles and they slept together.

Rosalie and Michael went their separate ways after their night together. When they ran into each other several weeks later, Michael offered Rosalie a nursing position at the Elm Street clinic. Rosalie declined and admitted that she had only posed a nurse under the duress of Nina's blackmail. Michael appreciated her honesty and asked Rosalie to work for him at ELQ as his personal assistant. She accepted the offer and later secretly checked in with her real boss, Helena Cassadine, and informed Helena that she had secured the position at ELQ as directed.