Classic public domain film, digitally preserved and free to stream forever.
The Invisible Killer (1939) is a crime mystery in which a series of murders are committed by an unseen assassin who can kill his victims over the telephone using a deadly sound wave device. A tenacious female reporter teams up with a detective to expose the killer before more victims fall.
Starring Grace Bradley, Roland Drew, and William Newell. This film is in the public domain and free to watch, download, and share.