A thrillseeker finds himself drawn into a game company, presumably as a playtester, given the title of the episode. For those of you not aware of what a playtester does, they're hired by game developers to perform test plays of games to spot any bugs or design flaws, which the devs then fix and remove.

However, this is Black Mirror, so things aren't so simple. The showrunners look to use horror conventions, so something bad is going to happen. Like any good horror, what that is is kept a mystery, which this featurette only hints at.

You can catch Playtest and the rest of Black Mirror season three in its entirety on 21 October, a week from today.