A gang of thieves gather at a safe house following a robbery, but a detective is on their trail.
Criminals pose as ghosts to scare a lighthouse keeper on the Welsh coast, in attempt to distract him. Jim Pearce deliberately maroons himself on the rock along with Alice Bright. When the light is later smashed, Jim reveals that his brother’s ship is the wreckers’ latest target, while Alice is a detective sent to investigate.
When a photograph is taken at the scene of a murder, the camera is tossed out of a castle window to destroy the evidence and lands in the back of a passing car belonging to chemist John Gray who becomes amateur sleuth after developing the film and goes in search of the woman captured by the photograph. When the camera is stolen from his laboratory, Gray's suspicions are further aroused.
