Black Mirror: Bandersnatch is a Netflix film directed by David Slade and will be released on December 28. The synopsis for the movie reads as follows: “In 1984, a young programmer begins to question reality as he adapts a sprawling fantasy novel into a video game and soon faces a mind-mangling challenge. Welcome back.” The trailer is a chilling tease that headlines the film as a “Black Mirror Event”. There is already a landing page on Netflix for the film coming out Friday.

Bandersnatch is a stand-alone full-length film with Season 5 of Charlie Brooker’s Black Mirror sci-fi series still in the works. The cast consists of Craig Parkinson, Alice Lowe, Will Poulter, Asim Chaudhry, and Fionn Whitehead from Dunkirk.

In the film, Stefan (Whitehead) creates a computer game with colleagues which alters his reality. In the trailer, Stefan is seen downing a daily dose of pills and discarding them later, resulting in speculation of his mental state to begin with. A theme seems to be about change, changing one’s life and even one’s past.

A Bandersnatch is a creature from Lewis Carroll’s novel, Through the Looking Glass. Creatures with this name and references to the word were in various games, shows, and movies.