Dr. Paul Carruthers feels bitter at being betrayed by his employers, Heath and Morton, when they became rich as a result of a product he devised. He gains revenge by electrically enlarging bats and sending them out to kill his … Bela Lugosi, Suzanne Kaaren, Dave O'Brien, Guy Usher, Yolande Donlan, Donald Kerr, Edmund Mortimer Added on Amazon Prime 2023-03-29.