Which 2015 horror film was Anya Taylor-Joy's breakthrough role?

Anya Taylor-Joy's breakthrough role was in the 2015 horror film The Witch.

She plays Thomasin, the eldest daughter in a Puritan family whose isolation on the edge of a New England forest leads to religious fear, suspicion, and supernatural terror. The film was written and directed by Robert Eggers in his feature directorial debut and is also styled as The VVitch: A New-England Folktale.

The Witch premiered at the 2015 Sundance Film Festival, where Eggers won the directing award in the U.S. dramatic competition. Taylor-Joy's performance drew immediate attention and established her as a major young screen presence. The film is often described as folk horror or a historical horror film rather than a conventional jump-scare movie.

Morgan and Split came later, in 2016 and 2017. They helped broaden her profile, but The Witch remains the canonical answer for her breakthrough role and her first major feature-film success.