Faith Rosco arrived in Port Charles in late 2002 to take down rival mobster, Sonny Corinthos . She partnered up with Ned Ashton , who blamed Sonny for the death of Kristina Cassadine . Ned soon became fed up with her, and ended their partnership.
Rosco found a new partner in Sonny's new lawyer Ric Lansing . When Ric attempted to end his partnership with Faith, she did not want to let him go. Encouraged by their one night stand, Faith continued to pursue Ric, though he to rejected her advances at every turn. After realizing Ric had fallen in love and eloped with Elizabeth Webber , Faith tried to run her off. When she found out Elizabeth was pregnant, she tricked Elizabeth into a supposed meeting with Sonny, As Liz's back was turned, she pushed her down the stairs. Elizabeth had a miscarriage. Ric blamed Sonny.
Rosco continually tried to convince Ric he would not be happy with Elizabeth. She went as far as breaking into Ric and Liz's home to poison Liz. Elizabeth survived. Ric found out about what Faith did He set her up to confess while the PCPD listened in. To avoid going to prison, Faith made a deal with the FBI to bring down Lorenzo Alcazar . Part of the deal was to pose as Sonny's mistress.
She turned on Sonny, and teamed up with Alcazar. The two planned to bring Sonny's ex-wife, Lily Rivera Corinthos , "back from the dead" to haunt him. The plan fell through. Faith begun working on her own plan, and at the next meeting of the five families, Faith had them all killed. She gloated about her accomplishment to Sonny, until Sonny informed her Jason survived the shooting. Faith panicked and offered to work with him against Alcazar. Sonny refused and pulled out his gun - but he could not seem to pull the trigger.
Faith, next became involved with Luke Spencer , Skye Chandler , and their casino, The Haunted Star. After she won a poker game against Luke, she became a partner in the casino. Worried, Skye hired Justus Ward to protect Luke's ownership rights while he was out of town. It was revealed Justus and Faith had a past together. Justus had represented Faith's ex-boyfriend, and they had an affair. Faith's ex was convicted and killed in prison. She believed Justus intentionally sent her boyfriend to jail so that he could be with her. Justus denied this.
Rosco, realizing he was at the end of her rope, went to Sonny to beg for her life. Through eavesdropping, she found he was the real father of Sam McCall's baby and planned to use it to her advantage. Sonny eventually came clean to his wife, Carly. Faith lost her leverage.
Rosco went to Alcazar to help her leave town. Alcazar secretly planned to blow up the yacht she was on and frame Jason and Sonny for her murder. Alcazar's plan failed when the PCPD found Faith alive in the harbor. She was arrested once again, and begged Justus to help her. Justus agreed, feeling the need to make up for their past. When a prison inmate stabbed Faith, she was rushed to General Hospital , and from there escaped. Justus hid her in the basement of the Quartermaine mansion. There, she confessed her love for Justus and they made love. Soon Faith met her end in March 2005 where she was shot and killed by an assassin hired by AJ Quartermaine . She later made appearances as hallucinations made by Carly Corinthos, during her severe mental breakdown.