Garth Marenghi's Darkplace is a British horror parody television series created by Richard Ayoade and Matthew Holness for Channel 4. The show focuses on fictional horror author Garth Marenghi (played by Holness) and his publisher Dean Learner (played by Ayoade), characters who originated in the stage show Garth Marenghi's Fright Knight.

The series is presented as a special release of the fictional television series Darkplace. Within the reality of the show, Darkplace was produced in the 1980s for Channel 4, but never broadcast anywhere but Peru, eventually becoming a lost series. Saved footage has recently resurfaced, with Marenghi republishing with the intent of gaining interest from a modern audience. The "original footage" of the show is intercut or bookended with commentary from many of the "original" cast, where characters such as Marenghi and Learner reflect on what it was like to make the show. Darkplace parodies the fashion, special effects, production gaffes, and music of low-budget '80s television, as well as the arrogant attitude of certain writers and performers.

Darkplace was broadcast in a late-night timeslot, with very little advertising, and met with poor viewing figures. It built up a significant internet following, leading Channel 4 to repeat the series and produce a DVD release. In 2005, Channel 4's Film4 asked Holness and Ayoade to write a script for a film version of the series, but the project never saw further development.

The show was later broadcast in the United States on the Sci-Fi Channel and Adult Swim and is available to stream on Peacock.