The cast of The Lighthouse, director Robert Eggers’s follow-up to The Witch, is composed of two men: Willem Dafoe and Robert Pattinson. In the film, which played at this year’s Toronto International Film Festival, the pair play lighthouse keepers — one a surly seasoned veteran with many a story to spin, and the other a novice with secrets aplenty and a propensity for silence. For around 98% of the film’s running time, they are the only two people in the movie. But then there is a mermaid. She doesn’t turn up for long, but she certainly leaves an impression.