Fisher: Life is always the cause of death.
He has a dark personality and often makes pessimistic remarks, a contrast to the other interns. This has caused him some friction and some inability to become friends with the other interns and staff. His thesis was on how bones scatter upon falling from high heights. He had once been on a Suicide Hotline, where he got the idea, and volunteers at a sperm bank. However, he is very successful with women, as he boasted about hitting close to 100. His skill with women was proven in an episode where he got intimate with a random girl outside the theater where the movie Avatar, which Joel Moore has a part in, was premiering.
In "The Princess and the Pear", he admitted to being a "geek" and went undercover at Imagicon, a fantasy convention for a case. His future at the Jeffersonian however, was placed in doubt after he admitted to sleeping with one of the suspects.
In "The Critic in the Cabernet", he offers to let Brennan use his "discount sperm" for the baby she decides to have. He is turned down, however, in favor of Booth. Booth is against the idea of Brennan having Fisher's children because if that were to happen, it would be like "giving birth to the spawn of Satan."
In the fourth season finale (The End in the Beginning), Fisher was re-imagined as the bitter chef at Booth and Brennan's night club.
In "The Gamer in the Grease," Fisher has invited Sweets and Hodgins to see an exclusive showing of Avatar. He admitted to sleeping with nearly 100 women.
In The Mastodon in the Room, Caroline reveals that Fisher checked himself into a clinic with a case of the "hopeless vapors", but he was re-instated in The Daredevil in the Mold, where he works to cure himself of his depression, listening to calming beach noise and drinking foul smelling tea.
He was in another institution and now lives with his mother as mentioned in 'The Twist in the Twister'.
In "The Method in the Madness" he figured out that the killer of Jessica Pearson copied Jack the Ripper. In "The Patriot in Purgatory" he was one of the five squinterns to help solve the 9/11 case. In The But in the Joke reveals that Fisher is an occasional stand-up comic who has some notoriety on the underground scene. His act is made of "raw, unfiltered honesty".
When Hodgins discovers that he has a brother named Jeffrey who turned out to be mentally ill in "The Heiress in the Hill", Fisher tells him how he understands how Hodgins feels because of how he spent time in a loony bin. He tells Hodgins that he needs to be happy for his brother now that Jeffrey found Jack. In "The Recluse in the Recliner" he has a new therapist. According to Hodgins, "Fisher just realized that murderers are bad."
In The Secret in the Service, Fisher returns to the Jeffersonian to aid in the investigation of a murdered Secret Service agent, since Brennan was sick. He is also revealed to have gotten his doctorate. Though he wouldn't admit it himself, Angela figured out that he is the college tutor of the President's daughter, which turns out to be the reason he was recommended for the case.
In The Tutor in the Tussle, Brennan discovered that Fisher was a fan of her novels and he even made a fan fiction at some point called "The Perspicacity in the Bones" which was about "a tormented intern who had an affair with his boss." Brennan agreed not to tell anyone about it and she rubbed in that there are some things that bring him joy despite Fisher's normally apathetic attitude. Fisher's reaction was to comment that he was in a hell of his own making to Brennan's own joy.
- He is the best squintern at establishing the estimates of bone remodeling.
- Fisher's absence in Season 10 can be attributed to the actor's role as the more positive medical intern Lucas Wahl in forensic drama Forever.
- In the episode The Gamer in the Grease, Fisher, along with Sweets, and Hodgins, camps out in a theater line to see Avatar. Joel David Moore, who plays Fisher, also played Norm in Avatar. As an in-joke, or ironic twist, Fisher misses the premiere while he's having sex in the tent as everyone else enters the theater.
- In The Patriot in Purgatory, Fisher decides to lead a pseudo therapy session after Wendell breaks and has an outburst. He starts by stating he was a senior in 2001 when the news broke, making his year of birth 1984, assuming he didn't skip any grades.