From Wikipedia:

The Quiz Broadcast: a post-apocalyptic television quiz show hosted by Mitchell (who constantly reminds viewers to “remain indoors”) and transmitted by the British Emergency Broadcasting System. The show is being aired in the immediate years after “The Event”, an unexplained disaster that left most of the human race dead, including all of the children. The sickly contestants on the show are survivors “trying to enjoy themselves” whilst avoiding any traumatic memories of “the Event”–Peter (a blind man played by Webb), Sheila, and Unknown Male 282. Prizes in the game consist of the sparse food and fuel supplies they have in their bunker. The questions asked often revolve around “pre-Event” subject matter, which the contestants have little to no knowledge of, while later sketches demonstrate the increasing deterioration of society, morale and health, and suggest that a cannibalistic race referred to as “Them” had overrun the area. The sketch ends on a somber note with Peter and the host being the last survivors of the bunker and possibly even the human race; Peter remains hopeful that help will come, but the host knows that it won’t. In March 2020, 13 years after the original broadcast, these sketches and the ‘Remain Indoors’ banner in particular, began trending heavily on social media in light of the Coronavirus pandemic and the associated national lockdowns.