2001 Movie Edit
Jezzie Flannigan was a member of the Secret Service working for Senator Hank Rose, mainly watching over his 12-year-old daughter, Megan, who is later kidnapped by her teacher, Gary Soneji. Flannigan partners with Alex Cross to find Megan, but as the film progresses, it is revealed that Soneji was set up, and Flannigan was the mastermind, with fellow Secret Service Agent (and lover), Ben Devine, as her accomplice. Devine had taken Megan from Soneji's boat and held her captive, and also took possession of $10 million in diamonds that Cross delivered to Soneji as part of his list of demands.
Flannigan's villainous reveal came when she reunited with Devine at a farmhouse where Megan is held captive, but she warns him that Cross will be on their trail after killing Soneji, which was done after realizing that he no longer had possession of Megan anymore. At that moment, the evil Flannigan kills Devine with a single shot to his head, after revealing that he's the only one under suspicion. She later searched for Megan with the intent to kill her as well, but she is later caught and confronted by Cross, who shoots and kills her.
In the novel, Flanagan is also portrayed as the villainous mastermind, but unlike in the movie, she engaged in a romantic tryst with Cross. Cross confronted Flanagan over her betrayal while they were on vacation together, and after admitting everything in a taped conversation, Flanagan is arrested and later executed for her crimes.