Inspector Spacetime

Two cosplayers dressed as Constable Reggie and the Inspector from Inspector Spacetime at San Diego Comic-Con. (COMIC: Selfie)

Behind the scenes
The NBC comedy featured Inspector Spacetime as a show-within-a-show which follows the eponymous Inspector and his Constables as they travel through time and space in their  X-7 Dimensionizer time booth, fighting enemies such as the "Blorgons", armed only with a quantum spanner, an analogue to the sonic screwdriver. A British programme, Inspector Spacetime is said to have begun in 1962, thus making it the oldest sci-fi show on television. Several webcast episodes of Inspector Spacetime were later created, under the comical title of Untited Web Series About a Space Traveler Who Can Also Travel Through Time, outside of a Community context; this series introduced a companion to the Inspector named Piper Tate, in reference to the last names of Billie Piper and Catherine Tate.

The cosplayers in Selfie are actually dressed as Troy and Abed from Community when they cosplayed Constable Reggie and the Inspector from the 1980s "Inspector Spacetime Christmas Special". (The colouring of Constable Reggie's costume is inaccurate.)

Inspector Spacetime was distantly acknowledged by Doctor Who some years before the comics cameo, in the form of the Official Doctor Who Tumblr showcasing a fan-made poster for Inspector Spacetime in 2011 as an example of Doctor Who fanart.