Undressed is a novel written by Annie Wilson and publish by Amanda Barnard.xx
The book is based on her life including her past relationships with Liam and Patrick, except she uses other names, like 'Annabelle' for herself, 'Leo the brooding loner' for Liam, and 'Patterson' for Patrick. She writes the story anonymously, although Silver is able to tell it is her by only reading half a page and Liam realises it's her too after reading it at the premiere and thinks Annie uses him like Sydney, Vanessa, and Ashley did, and doesn't read the end of the book where Annie writes them living happily together.
Naomi does not know it was Annie and described it as sexy and filthy. She was planning the party and wanted to make it amazing by revealing Author X. Naomi asks Annie to help. Annie gives her the name of someone who moved away 2 years ago and when Naomi finds out, she decides to figure it out at the premiere by watching Jordan and Amanda. Naomi thinks she knows who it is so she confronts the girl who she thinks is the author, Elizabeth, after she was secretive when talking to Naomi. Annie ties to stop her but Naomi won't listen. Elizabeth also tries to tell Naomi that she had nothing to do with the book, but Noami says that she has nothing to be ashamed of and "If I were you, I would hold that book up high and say 'I am Author X, and I am proud to be a whore." Jordan reveals that Elizabeth is his sister. Annie then tells Naomi that she is Author X. Undressed causes a lot of problems for Annie and Liam.
Liam was a celebrity guest at the launch and read a chapter from Undressed, specifically an Annabelle and Leo chapter. Liam immediately knew it was about him and refuses to talk to Annie. Liam thinks that Annie was using him like every other girl has. After their fight, Patrick knocks on their door, telling Annie that if she exposes herself as the author, his wife will find out it was he is Patterson and that if she ruins his family, he will ruin hers. Annie tells Dixon the truth about how she paid for his rehab and he storms out. He later find Annie in New York before her interview and tells her to tell the truth, he can handle Patrick. Annie reveals herself on TV as Author X. Patrick confronts Annie in the hotel lobby, saying she will pay for this and that she is a bitch, Annie replies by saying "payback is the bitch, not me."
In the series finale, Liam reads the end of the book, which revealed Annies feeling towards him and drives after the plane that Annie was on with Naomi and Jordan, which was going to Washingtnon, DC then Annie was taking a plane to Paris from there for her European book tour. Annie got on the plane but Liam arrives just in time to stop her leaving which was like the end of the book where Annabelle and Leo drive off in his motorcycle together. Annie mentioned this earlier when she said she tried to write her own happy ending but it didn't work, but eventually she got her happy ending with Liam as the two are now engaged and live happily ever after