Now that footage from Jon Watts' "Clown" has made you thoroughly terrified of the circus entertainers, the new trailer for "Lights Out" will reinforce any reservations you might have about the dark.

Produced by James Wan, the supernatural horror film stars Teresa Palmer as Rebecca who, as a child, was never sure what was and wasn't real when the lights went out. Now she's worried that her little brother might be haunted by the same supernatural entity, which has a mysterious attachment to their mother.

The feature directorial debut of David F. Sandberg, and based on his short film of the same name, "Lights Out" also stars Gabriel Bateman, Billy Burke, Alexander DiPersia and Maria Bello. The film opens July 22.