The pilot episode of Dirk Gently is the first broadcast episode of the BBC Four television series inspired by Douglas Adams's novel Dirk Gently's Holistic Detective Agency. First broadcast on 16 December 2010 and repeated throughout the Christmas period, it was written by Howard Overman and stars Stephen Mangan as holistic detective Dirk Gently and Darren Boyd as his sidekick Richard Macduff. Recurring actors include Helen Baxendale as Susan Harmison, Jason Watkins as DI Gilks and Lisa Jackson as Janice Pearce.
The episode opens with private investigator Dirk Gently asking the elderly Mrs Jordan for payment in his ongoing search for her missing cat Henry. Leaving Mrs Jordan's house, he witnesses his old friend Richard McDuff breaking into her neighbour's house. It transpires that Richard was attempting to steal a laptop belonging to his girlfriend Susan Harmison, whom Richard has just split up with and has sent an insulting e-mail, which he now regrets. On spotting clues suggesting the presence of the missing cat, they follow it into a nearby warehouse and encounter a bizarre machine. However, an explosion destroys the machine before they can investigate. It later transpires that the warehouse belongs to their fellow university alumnus, Gordon Way, a millionaire computer expert (and Susan's former suitor at college) who has gone missing. Dirk soon deduces that events all seem to connect with the 5 December 1994, as that is the date where Susan broke up with Gordon because he missed a date (due to Dirk accidentally running Gordon over in his Austin Princess, when trying to escape an angry Richard), and the date on which Mrs Jordan's first cat, George, walked into her house. Recalling the equipment that he and Richard found in a warehouse near Susan's house, Dirk deduces that Gordon Way had developed a time machine to go back and save his relationship with Susan before it went wrong, with Mrs Jordan's cat getting into the machine with him and being sent back to the past (meaning that Mrs Jordan's two cats were actually the same cat). Gordon, it is revealed, was killed in the past by Mrs Jordan after he saw her with her husband's dead body (Mrs Jordan having killed her husband when he began to mistreat the 'new' cat). Mrs Jordan subsequently commits suicide after tricking Dirk, Richard and Susan into leaving her so that she will not have to go to prison. At the episode's conclusion, Dirk has tricked Richard, via hypnosis, into investing his redundancy money into Dirk's firm, allowing Dirk to go to Barbados on an "investigation" while Richard is left as Dirk's new partner in the detective agency.