23. 'White Christmas': The 2014 Christmas special was the final episode of the show to air on the UK’s Channel 4, and probably served to prove that 'Black Mirror' had gone as far as it could with a traditional broadcaster. 'White Christmas' packs three separate stories into its 74-minute run time, all dealing with themes that have been explored in more depth in standalone episodes before or since. Brooker suggested that the inspiration for the three-story, feature-length anthology was the 1983 'Twilight Zone' movie, which was pretty terrible, so could explain why 'White Christmas' is propping up our list. Netflix

‘Black Mirror’ episodes to rewatch as season six is in the works