Gumshoe was an artificial reality game created by Interstella Action Games. It was a favourite of Dave Lister, who obtained it from a derelict ship that had been devastated by the Simulant Battle Cruiser. Dave Lister often played Gumshoe aboard Starbug and had sex with the villainess of the game, Loretta.
It was a film noir-inspired role-playing game, where two of the playable characters known were Philip (a private eye whom Lister played, mainly so he could have sex with Loretta, a "psychopathic schizophrenic, serial killing femme fatale") and Sammy the Squib (a Mafia hitman whom Kryten played in order to talk to Lister).
Gumshoe was played by as many as four people, who could take the roles of different characters: Philip, Sammy, a blonde woman and a police officer.
The exact setting was ambiguous, being somewhere in America during the first half of the 20th Century, possibly in a Great Depression/Prohibition environment. The characters had to catch criminals, such as serial killer Loretta. The gameplay was in black and white, typical for film noir.
Lister and Kryten play Gumshoe
Lister had played Gumshoe several times, mostly because he could have sex with Loretta. He knew that she was a psychopath and had several other lovers, but he still found her irresistible. Kryten reluctantly joined him, but only to tell him about the rogue simulant zone they had entered. Lister and Loretta were engaged in an activity that had made the windows of their car steam up. Lister insisted that he could be finished in as little as 5 minutes if he kept his hat on. Kryten was adamant that Starbug needed to go into silent running mode. They left Loretta and exited the game. ("Gunmen of the Apocalypse", Series VI)