A downtrodden, tough female private eye, Toby Merck, tries to regain control of her life - before she loses it during an investigation into a dangerous case of murder, sex and drugs.

Electrical overload at the Throbbing Video Company office alows an alien force into the phone lines. The force becomes a sound wave and enters the body of an electrician who then goes on a rampage. When the electrician is killed, the force transfers to another body and so on.