Gorilla At Large is a story about a detective set out to solve a murder case. The murder takes place at The Garden of Evil, a carnival with a gorilla act as the main attraction. However, an ex-employee has been found dead in the cell that contains the live gorilla. The gorilla, called Goliath, is the first to be blamed for the death, but Detective Garrison (Lee J. Cobb) suspects foul play at the carnival. He finds many suspects involved with the carnival that would have something to gain from the ex-employee's death. Garrison investigates everybody from the Gorilla's trainer to the worker who has taken the dead employee's job. Now, more murders are taking place and Detective Garrison still hasn't found the killer. He gets increasingly clumsy as he grows more desperate to solve the case. Will Detective Garrison be able to catch the murderer of The Garden of Evil before more people are found dead?