Jacqueline Logan stars as Paula, a beautiful and fearless circus leopard trainer. Working hand-in-glove with the police, Paula joins a circus where several murders have occurred. Among the suspects is gorilla trainer Caesar (Alan Hale Sr.), who previously in the picture had saved Paula's life. Nonetheless, when Caesar is revealed to be the murderer, he unleashes one of his killer apes with orders to tear Paula and her sweetheart Chris (Robert Armstrong) apart. Luckily, Paula proves to be as adept at "staring down" the ape as she is at pacifying the big cats.