One of his patients was Walter Kovacs, who'd been arrested by New York City Police at the former tenement of Edgar Jacobi, and accused for Jacobi's murder. Long looked forward to that case, and hoped that the extreme nature of Rorschach's actions would help him identify a new syndrome that would apply to the Costumed adventurer phenomenon. He prepared to take meticulous notes as he would write a book on this case.
As he entered NY State Pen, he encountered journalists to whom he told that he was he was confident and optimistic.
On the first day he was visibly disturbed by Kovacs' stance as he examined him with Rorschach blot tests and Kovacs pretended to show improvement. That night he studied his early life and Gloria told him not to lose himself in that case as it would ruin his cheerful disposition. Mal replied that their happy and content life could not change with his job.
The next day Mal started taking Gopain pills produced by Veidt Enterprises. In their next session Kovacs called him fat and content, knowing nothing about emotional or mental pain. He narrated his youth and how the murder of Kitty Genovese affected his view on society; Kovacs saw beyond Long's pretense of caring and wanting to help, as his interest was Kovacs' fame which would boost his reputation. That afternoon he got a call that Kovacs had thrown hot oil on another inmate, and realized that his optimism was unfounded. He spent the night with coffee and an additional bottle of Pain Away pills, trying to concentrate on the case, Gloria complaining that she didn't get the attention she deserved from him.
Kovacs relates the story of his transformation into his vigilante persona, Rorschach, to Long during a lengthy conversation about his crime-fighting but Malcolm couldn't understand what exactly compelled him and sent him over the edge, and wanted to show him that his views about life were wrong. On his way home he bought a New York Gazette from Bernard who pointed out excitedly that the man in the news was his customer. He returned home disturbed by the Hiroshima lovers graffiti and the news about Russians entering Afghanistan. That night Gloria attempted to sweeten things.
The next day Kovacs tells Long that his psychological breakdown came as a result of his investigation of the kidnapping of Blair Roche, a six-year-old girl, whose captor, Gerald Anthony Grice, butchered and fed her remains to his two German Shepards. On his way home he passed by a black Watch seller and bought a newspaper about Richard M. Nixon's response to the Soviets; and an article on nuclear alert procedure. Gloria had attempted to bring Malcolm to his senses by arranging a dinner with Randy and Diana. The guests start to tease Long about Kovacs. Unamused, Long tells them in detail about Grice's murder of Roche and how he disposed of the girl's body. Diana finds a pretense to leave early, then Gloria berates him and leaves him. He sat alone staring at a Rorscach inkblot, reminding him of the gross sight of a dead cat, and then the empty meaningless blackness of Rorschach's reality.
He resigned shortly before the riots in the prison.
Later Long and his wife have separated and are attempting to make amends when Malcolm witnesses Joey and Aline fighting. Long tries to separate Joey and Aline ; they are all killed minutes later when Adrian Veidt's monstrous alien creature is teleported nearby.
According to Gloria, he was one of the nicest and most positive persons. He liked to help people but Kovacs saw through this facade and understood that he was also ambitious. Long himself becomes affected by Kovacs. The intensity of Kovacs story causes Long to become slightly obsessed with the case. His conformed and content life could not stand against the dark reality and the case has a damaging effect on his marriage.
The film version of Malcolm Long is not as cheerful and as optimistic as he is in the graphic novel and is only seen in a few scenes; when interviewing Rorschach (after which he tells the guard that he cannot help him).
During the prison riot he hides in a storage room and meets Rorschach again looking for his gear. As Rorschach wears his mask, he says "Tell me doctor, what do you see?" showing the shapes on its surface. He is seen near the end of the movie when he is killed by the explosion. His wife and personal life are neither seen nor mentioned.
A movie prop with Rorschach's case file mentions the name Dr. Terrence Roberts.