Xavier "X" Daniels was a criminal who used to live in Tree Hill. He was responsible for the attack on Brooke Davis and for the murder of Quentin Fields and, after taking Brooke's foster daughter Sam Walker and his brother Jack hostage, he was finally brought to justice by Brooke. Years later, he is released and begin to harass Brooke. After some time, he attacked her a second time but Brooke once again conquers him.
After being left by their parents, Xavier resorted to a life alone with his brother Jack Daniels. Together they began a struggle through life with not many luxuries. Xavier was often violent towards Jack leading him to stay out of the house as often as he could and Xavier grew used to being alone.
When his brother, Jack Daniels with friend Sam Walker, Xavier hears of how Sam was caught shoplifting at the store Clothes Over Bros, Xavier listens to Sam calling her names and saying that someone has to put her in her place. With this in mind, that night, Xavier goes into Brooke's store with a mask on and attacks her. He knocks her over a sofa in her store and begins beating the helpless woman. He stole Brooke's sketches and also ended his attack by telling Brooke to 'Have a nice night.' After the attack, Brooke is left traumatized and feels insecure in herself and thus resorting to carry around a gun and training to fight back for the day she finds her attacker. She also decides not to report the crime to the police due to paparazzi interference and not wanting to involve anyone else. After a successful attack on Brooke's store, Xavier continues breaking the law and robs a gas station. After killing a worker at the gas station, Xavier is shocked when a person arrives to pay for his gas. Quentin, a high school student and promising basketball player, walks in the shop and goes to pay, but notices something is wrong with Xavier who is at the counter. Quentin notices the dead worker behind the counter and looks up in shock as Xavier points a gun at him and hammily tells him to have a nice night. He shoots the gun, killing Quentin and leaving a string of grief around the town of Tree Hill. Sam eventually finds out from Jack that it was Xavier who attacked Brooke because of what she said. She tells Brooke that night of the attack she caused and Brooke lets Sam leave. ("Touch Me I'm Going to Scream, Part 1").("One Million Billionth of a Millisecond on a Sunday Morning") ("You Have to Be Joking (Autopsy of the Devil's Brain)")
Xavier spends the following days hidden away in order to prevent himself from being caught by the police and is successful in his efforts. His brother, Jack, gets more comfortable with his friend Sam Walker and asks Xavier for her to stay with them, as she has had an argument with Brooke Davis. Xavier agrees as he picks Sam up with her not knowing the danger she is about to be put in. After spending the night at Xavier's, Sam wakes up to find him staring over him. Frightened, she wakes up, thanks him and grabs her bag to leave. But Xavier assures stops her and tells her that he knows she stole the sketches and wishes she never went through his stuff as now he is not happy. Sam assures him that she never told Brooke who stole the sketches as Xavier asks if she felt guilty towards Brooke. Sam tells Xavier how good she was to her for putting her in the nice, but Xavier takes it as she is saying that Brooke kept her from people like him and Jack. He tells Sam that he used to like her but does not like people who forget where they are from. Jack interrupts them telling Xavier to leave Sam alone, but Xavier turns around and hits him. Sam attempts to run as Xavier knocks her to the floor and tells the two kids that they need some time to think about what they have done and locks them in the room. Xavier steals Sam's phone as he leaves them in the bedroom and as he locks them into the room, they try to escape. They try to climb out of the window and Jack gets out, however Xavier returns to find Sam climbing out the window. He grabs her and drags her back into the room and as Sam shouts for Jack, he runs off and leaves Xavier with Sam. After her attempt, Xavier ties her up.("Things a Mama Don't Know")
After frantically looking for Sam, Brooke remembers that she spent a lot of time with Jack. She finds out where he lives and races to his house. As she knocks on the door, Xavier sees who it is. He goes into the bedroom and puts Sam in a cupboard. Tied up, Sam is told to not make a sound. Xavier then goes to answer the door and tells Brooke that he does not know where Jack or Sam is. Xavier laughs that they might be having sex and that he does not follow what Jack does. As they talk, Xavier compliments Brooke and the uncomfortable atmosphere and unusual comment, makes Brooke more curious. As she goes to leave, Xavier asks if she feels good to take in a child like him as Brooke says that he does not know her. She leaves as Xavier tells her to have a nice night. As he closes the door, Brooke realizes that he is the man that attacked her. She runs back up to the door and begins slamming on the door. As he answers again, Brooke sprays him with pepper spray in the eyes and demands to know where Sam is and kicks him to the floor. She runs into the house screaming for Sam. She runs into the bedroom and eventually finds Sam. As she promises Sam she is not going to leave her and everything will be okay, Xavier comes up behind her and pulls her up by the hair. Brooke begins to fight back and spits in his face as Xavier strangles her against the wall. She eventually breaks free and runs through the house as Xavier follows and trips her up. They both crawl as Brooke races for her purse and grabs the gun out of it and aims it at Xavier. Brooke tells him that she is not the same girl he met in the store and that he ruined her life. She prepares to shoot as Jack, Julian and Sam run in the door. She is about to shoot as Sam asks her not to as she needs her. She calls Brooke mom and Brooke lowers the gun. She tells Xavier that he is not worth her time and especially not her life. She hits him over the head with gun and as she knocks him out, tells him to have a good night.("Things a Mama Don't Know")
Following Sam being rescued, Xavier is sent to prison for an unknown amount of time and the police investigate his the amount of crimes he has committed, also revealing to people that he killed Quentin Fields. After being put in prison, Xavier leaves Jack who is eventually fostered by parents up in Charlotte and arranges to meet with his new girlfriend, Sam with seemingly no intentions of keeping in contact with Xavier.("Things a Mama Don't Know")
Xavier was released from prison against Brooke's notice. Before his departure he asked to talk with her and told that he had changed. But Brooke didn't believe him and tried to prevent him from leaving jail, however, he was released. Xavier began to harass Brooke's family, coming to her cafe and former store before attacking her. She is saved by Tara Richards, who tazes him in the back while he is strangling Brooke. Brooke demands for the tazer and unleashes her fury on Xavier by tazing him in the heart. She then calls the police and Xavier is locked up for good.
- Family: Xavier Daniels/Family
Xavier's parents were absent throughout his life and he was forced to spend his life alone and often taking care of his younger brother Jack. They managed to get a house although it was unknown whether Xavier had a job. As Jack grew up, Xavier was used to Jack's constant coming and going from their house. Eventually, their relationship turned violent when Xavier began hitting Jack. Even though this occured, Jack still relied on Xavier and loved his brother very much and both of them looked after each other and wanted the best for each other.
Not much is known about Xavier's personal life. It is unknown whether he had had a partner before or whether he had been single all of his life. However, he showed a lack of communication skills with the opposite sex when complimenting Brooke Davis on her appearance during the missing of her foster daughter, Sam Walker. Through this comment, Brooke was made very uncomfortable. Xavier also laughed that his brother, Jack may have been having sex with Sam Walker, again making Brooke very uncomfortable.
- Although Xavier is usually referred to with the surname "Daniels", he is called "Xavier Walker" in a parole letter sent to Brooke, as seen on screen in the episode "Last Known Surroundings".
- It is unknown as to how long Xavier was imprisoned.
- Although his behavior hints so, it was also never confirmed of any mental issues that Xavier had.
- Jack and Xavier never discussed the reasons for their parents leaving them to live on their own.
- Xavier appeared to have no job but was able to live in a house with his brother with no income. It is likely he robbed Quentin and the person he killed earlier that night, and also robbed the store where he committed the murders.
- Of the 4 psycho stalkers (along with Ian Banks, Carrie and Katie Ryan), Xavier is the only one responsible for murder. The other 3 attempted murder, but were either intervened (Ian, Carrie) or their targets survived (Katie).