A quartet of murderous psychopaths break out of a mental hospital during a power blackout and lay siege to their doctor's house.
Jack Palance
Frank Hawkes
Donald Pleasence
Leo Bain
Martin Landau
Byron "Preacher" Sutcliff
Dwight Schultz
Dan Potter
Erland van Lidth
Ronald "Fatty" Elster
Deborah Hedwall
Nell Potter
Lee Taylor-Allan
Toni Potter
Phillip Clark
Tom Smith / Skaggs
