Howard Epps was the first serial killer featured on the show, debuting in the seventh episode of the first season.
Howard had an estimated IQ of 180. His mother, Marianne Epps, had, in her words, a glandular condition which made her highly obese. She was highly religious and tried to raise him the same way and keep him "pure". Whenever he went out with women, all of which his mother felt were "loose", she would make him bathe in ammonia "to wash their scent off". She also physically abused him regularly and would later lament not beating him more frequently. He tells Booth and Brennan that if he had regretted not making her his first victim. In adulthood, Howard became a serial killer. He was arrested after killing one of his victims, April Wright. Since the other bodies were not found, no connection was made. Most of his victims were young, blonde women. Epps would later tell Brennan that no young woman was 'pure'. There was no indication that he ever made his victims suffer until after his escape from prison which is when he also expanded his range of targets because he "felt the need to grow as a person".
Dr. Temperance Brennan: For all your faults, Mr. Epps, you were never interested in letting your victims suffer. You didn't torture them. You're not that kind of man. She's an innocent child.
Howard Epps: She's a young woman. And there's no such thing as an innocent woman. Look within yourself, you know I'm right.
Epps was introduced in the episode A Man on Death Row, where he was a prisoner scheduled to be executed in two days, while his lawyer enlisted Brennan and Booth to try and clear his name. They were successful in delaying his execution pending a further review of the evidence but this was only after discovering, after tracing the location where the murder he was accused of had been committed, that he was not only guilty but had killed multiple other victims; the execution was delayed only to try him for the other murders. While being questioned in the end of the episode, Epps explained that he read Brennan's book and saw a way out when he learned that she was working with Booth, who caught him the first time.
After thanking Doctor Brennan and Agent Booth for extending his life, as he had planned, Brennan turns to leave in disgust. As she does, Epps moves to grab her wrist. She responds by grabbing his wrist, and slamming it against the corner of the interview table, breaking it. She then walks away, without another word or backward glance.
Booth: She's not the one who needs protecting. Bones broke his wrist.
Dr. Temperance Brennan: He touched me with his creepy serial killer hands.
The prison doctors failed to properly set his wrist due to self-defense by Dr Brennan, which would later cause him some amount of pain. He began a relationship with a woman named Caroline, who knew he was guilty, but believed him to be a good person underneath it all. They got married, even though Howard was not attracted to her. He simply married her because it was the "best he could do" as an inmate. The two even planned to have a child together.
Epps: You know. Those hack doctors in the prison infirmary did a miserable job setting my wrist. It aches all the time. I don't have my full range of movement and let me tell you, when you're stuck in a prison cell for 23 hours a day there is only one thing you can do to pass the time. And I need my wrist.
Epps' second appearance was in the episode titled The Blonde in the Game where he is still in jail but has been directing an accomplice, Gil Lappin, to continue his crimes in his absence, leaving clues for Brennan and the team to solve to lead them to the next victims. Gil's murders were mostly consistent with Epps' own, except he tortured his victims by suspending them upside-down before beating them to death, something Epps never did. When Brennan and Booth corner Gil, Brennan is forced to shoot him to save the lives of Booth and the final victim. When questioned, Epps reveals that the objective of "the game" was to force Brennan to kill, something she has never done before, thus 'proving' his point about women all being guilty. He originally thought that it would be Booth that would kill Lappin, but after he discovered that it was Brennan who shot him, he thought that it was better that he could have hoped. As Epps had planned, Brennan feels deeply guilty for killing the man, but she eventually comes to terms with it thanks to Booth's advice.
In his final appearance of the series, The Man in the Cell, Epps successfully escapes from prison during a fire by killing a fireman, stealing his uniform, and leaving the body in his own cell. After Epps' escape, he becomes obsessed with Brennan. Using mind games, he makes her feel responsible for the deaths of his victims. He tests her and the rest of her team by leaving clues for them to discover, decipher, and follow to more victims; one of whom was Epps' ex-wife, Caroline, who broke it off with him after the events of The Blonde in the Game. He also leaves traps in the clues; Zack is caught in an explosion and Cam nearly dies during Caroline's autopsy after inhaling a deadly toxin that was hidden in the head. After being cornered in Brennan's apartment by her and Booth, Epps jumps off the balcony. He is temporarily spared from death by Booth, who grabs his hand as he falls over the railing. In the end, however, Epps lets go of Booth's hand which results in him falling to his death when Booth can no longer hold on. Booth had some trouble coping with his guilt over his self-perceived role in Epps's death, but he eventually overcame this with the aid of psychiatrist Doctor Gordon Wyatt, who helped him recognize that he could have done nothing to save Epps and that letting go of him was totally unintentional and inevitable.
Howard targeted blonde women in their late teens and early 20s (he associated them with purity) and killed them by bludgeoning them with a tire iron. Afterward, he tied the bodies' hands and feet together and buried them face down. His accomplice, Gil Lappin, copied Epps' M.O. and victim type almost perfectly, although he tortured his victims by suspending them upside-down before killing them. However, despite his preference for blondes, while in prison he married Caroline Epps, a brunette woman who was later his final victim. Epps' method of killing her was much different from the others. He had decapitated her alive, leaving her head in the fridge with a glass ball of poison that affected Camille Saroyan, and her body in a tanners shop with the poison on her body that triggered a pressure bomb when Booth and Zack Addy tried removing it and injuring themselves to help cure Saroyan.
- One unnamed victim
- Tami Randal
- Lauren Hathaway
- April Wright
- Henry Gerber (stabbed; survived but was paralyzed from the waist down)
- Donald Kent (firefighter; killed and burned for his uniform)
- Caroline Mapother-Epps (his ex-wife; decapitated)
- Camille Saroyan (poisoned but later cured)
- Zack Addy (almost blown up, but saved by Booth)
- Temperance Brennan (attempted)