If a director dies while their movie is under production - for example, the director had a sudden heart attack, what will happen to the movie? Will it still be produced and be in cinemas, or become cancelled? If the movie eventually appears in cinemas, who will become the new movie director?
Although somewhat rare in occurrence that there would be a single answer, it will generally depend on how far along in production and the circumstances. Since the director is mostly responsible for shooting the film, if filming has been completed, then often the studio will complete the editing and release of the film. This is the case when Joe Ranft co-director of the Pixar production Cars, died in a tragic car accident before production was completed.
If filming has not been completed, the studio may hire another director to complete filming who may or may not be credited, depending on the circumstances.