Hereditary ending explained

What happens

Peter is led to the treehouse, where the cult waits. They reveal that Paimon has been in Charlie all along and now passes into Peter. They crown him king, proving the whole family was manipulated from the start.

The last image

The cult kneels before Peter, newly crowned, in the treehouse.

What it says

The ending makes the title literal: damage is handed down, and the family never had real choices. They were figures in a model, like Annie's miniatures, arranged by unseen hands. The reveal gives the film's fatalism a face.