David James Fisher (1969-2044) played by Michael C Hall, is the middle Fisher child. He is four years younger than his older brother Nate, and at the beginning of the series both share a strained relationship, mostly due to David's jealousy over Nate's escape from the Fisher home, as well as his 'Golden Boy' image with their parents, Ruth and Nathaniel Sr. This relationship soothes after Nate decides to stay and help out with the family business, and are shown to have mended their relationship by the end of Season 1, and share a close bond by the end of Season 2 (Nate wishes David could come with him into surgery. They both sit together and later sobs over the possibility his brother might die). He seems to share a loving, if not a slightly strained relationship with his mother, Ruth. He and his father had a distant but loving relationship. He and Claire seem to have the closest bond in the family, as both often talk with each other about the events happening in their lives, their problems, and even once become high together. He also admits to Nate (who was high at the time) that he does like Brenda.
Before the series begins he was said to be engaged to Jennifer Mason. He lied to both her and himself about his sexuality, but later ended the relationship. He was also studying law, and hoped to leave the family business to become a successful lawyer. This was put on hold due to his ties to the family business, and became permanent after the death of his father in the pilot episode.
In the beginning of the series, David is dating police officer Keith Charles, whom he met at a church social function. Keith is an African American cop, who is proud of his sexuality, where David still struggles to accept his own. He refers to Keith as his 'racquetball partner' (although they don't start playing racquetball together until Season 2). He is offered the position of church deacon, taking over his father's position at the Episcopalian Church. He wonders whether to take the job. While grocery shopping with Keith, an impatient driver dubs them 'fags'. This enrages the usually sensitive and calm natured Keith, who threatens and even harms the man, which causes him to drive away in fear. David reprimands him, while simultaneously deciding to take the job as church deacon. Keith finally has enough with David's shame over his sexuality and breaks up with him. This devastates David, and he begins to engage in one night stands and risky sex (once having unprotected sex with a male prostitute in Las Vegas). He is caught by Keith who is now in a relationship with emergency medical technician Eddie, with whom he later moves in with, to David's despair. David is arrested in Las Vegas, and is let out by Keith, who is visibly disgusted but concerned with David's self-destructive nature. His sexuality is also guessed by Claire in the pilot episode when Keith comforts David, and by Nate and Brenda when he purposely outs himself to them, which surprises Nate but impressed Brenda. When a young homosexual man is murdered, it haunts David, and he begins to believe he will go to hell. He accepts who he is when he delivers a sermon as church deacon, and resigns afterward. He comes out to his mother, who guessed as much but refused to accept it. She becomes upset, especially after learning she is the last to know, and believes he didn't trust her enough to tell her. He tells her he does, but knew she would be disgusted by his sexuality. She becomes angry and tells him she will always love him. He apologises and both mend their relationship. Keith and David also mend their relationship, where Keith is visibly moved by David coming out.
In Season 2, David and Keith reconnect after Keith seeks comfort from David after killing a man on the job. Keith is conflicted over his family situation (his sister's drug abuse and neglect over her daughter, Taylor) and his relationship with Eddie (who he admits only ever wants to have sex) and his remaining feelings for David. David begins a relationship with Ben, a lawyer, but cannot shake his feelings for David. He later breaks up with him after Ben admits that he loves David, but David can't answer, stating he is 'in love with someone else' which causes Ben to storm out in anger. Keith also breaks up with Eddie and both become involved, with David quickly moving into Keith's apartment. The relationship becomes strained when a newly troubled and Keith (due to his family problems) gives David mixed signals, and even becomes verbally abusice. They take in Keith's neice, Taylor, and later plan to officially adopt her. But after he is suspended from work for excessive force, he sends Taylor to live with his parents, which devastates David. Keith and David engage in an argument when Keith mistakes David's tears (over his brother's impending operation) over frustration over their strained relationship. It ends in a struggle, and both engage in rough sex.
In Season 3, David and Keith are in couples councelling. David decides to join the Gay Men's Chorus of Los Angeles. David notices Keith's awkwardness when it comes to spending time with David's friends from the Chorus. This ends up in an argument, where Keith offers David and his friends to participate in a paintball game with his friends. It ends in the both of them losing. Keith's friend, Sarge, who is too inebriated to drive home, stays over and they participate in a three- way. They begin to participate in one-night stands, which causes David some discomfort. David and Keith visit his parents in San Diego after his great aunt's funeral. But David feels out of place, and is reprimanded by Keith when he jumps in to help him when he gets into a violent argument with his abusive father. He leaves, clearly hurt, and takes a bus back to Los Angeles. He meets up with his friend Patrick from his chorus group, and the two have sex. David stays with Nate (who is distraught over Lisa's disappearance) while avoiding Keith. He returns home, and both quickly engage in an argument where David finally stands up for himself and breaks up with Keith and moves back home. He encounters Keith at their church, and both have a long talk and mend their relationship.
After Lisa's death, David takes on the bulk of Lisa's funeral plans while Nate grieves. He helps his brother deceive Lisa's family by putting unclaimed cremains in the family urn, and allows Nate to bury her body as she wished. David and Keith decide to start their relationship over but on the condition they quit therapy and Keith quit his job as a security guard. David receives oral sex from a plumber, but both laugh it off, a considerable change to their previous relationship. While Keith is away (he is a private security agent for celebrities, and is assigned to pop star Celeste) David is kidnapped and held at gun point. Keith rushes home, but David assures him he can go back to work, and that he is fine. David begins to suffer panic attacks, and becomes increasingly emotionally unstable and lonely. He begins to drink heavily and begs Keith to become sexually exclusive, despite later on sleeping with Sarge again. Despite coming out at work, Celeste seduces him, and then fires him for the indiscretion. Keith confesses his infidelity and David fears Keith will leave him for a woman. David eventually confesses his fling with Sarge. The pressure builds until finally, David assaults a man in a restuarant. The victim implies that he will drop the lawsuit against David if Keith gives him a blowjob. He complies. The man then hires Keith for personal security. David faces his attacker in jail to put his trauma behind him.
In Season 5, David begins to refer to Keith as his husband. As they begin to settle down, they make plans to become parents. After a failed surrogacy attempt, they adopt orphans brothers Durrell and Anthony after David bonds with Anthony at an adoption fair. The boys suffer from trust issues, and Durrell proves to be rebellious due to his life in foster care. Keith considers returning them to the orphanage, but David insists on keeping them. Soon after they adopt the brothers, Nate dies and David falls a part. His panic attacks return, as well as his memories of his attacker. After six weeks, he is still unable to face business issues with his business partner (Rico) and Brenda, Nate's beneficiary. After David accidentally burns down their apartment, Keith asks he move elsewhere until he recovers. After a brief stay with his mother, both Keith and David buy both Rico and Brenda out. They redecorate the home and move in.
After the series ends, David teaches Durrell how to embalm, and he eventually joins the family business in his adulthood. In 2009, Keith and David are legally married, and remain together until Keith's murder (while on a job) in 2029. Durrell is seen seated with his wife and child, while Anthony is seen with his boyfriend (they are holding hands). David retires from Fisher and Sons in 2034, and Durrell carried on the business. He stars in many local community theatre productions. He later begins dating Raol Martinez, and are together until David's death at a family function in 2044, when David is 75. David's last vision is of a young and healthy Keith catching a football and smiling at him.