Black Mirror Season 7: Bête Noires twisty ending, explained

Bête Noire is a long way from the bleakest episode of Black Mirror Season 7, but its twist — or at least the sci-fi element of the episode — is probably one of the trickiest to get your head around.

The bulk of the episode plays out like a drama/mystery, only for the last 10 minutes to go impressively off the rails. So what happens at the ending of Bête Noire, and how does the device that Verity (Rosy McEwen) uses to alter reality actually work? We've done our best to break it down below.