What If...?

Nine episodes that each change one decision in a film you have seen, and follow what falls out of it.

The Watcher narrates, does not intervene, and introduces each episode as a timeline where a single moment went the other way. Peggy Carter takes the serum instead of Steve Rogers. T’Challa is abducted as a child instead of Peter Quill. A quantum virus reaches Earth and the Avengers become the outbreak.

The format’s strength is that it needs you to know the original. It is the first entry in this catalogue that is entirely about the rest of the catalogue, which is why it is the worst possible place to start and one of the better places to end up.