An Archeology Professor and antique collector, Laphin, goes trekking through a deep jungle to the Cambodian border to see an ancient palace with two guides. They see a crazy man who runs away when he sees them and drops a small wooden statue of monkey. They keep it. They travel on and come across a village whose inhabitants have all been violently killed by what seems to have been an animal. They leave the village and meet a starving man. They share their food with him and tell him about the statue and the village. He warns them that if they keep the statue which is of the legendary monkey monster named "Kong Koy" to cover it with a small holy cloth or face the "evil". He gives them the cloth and goes. They return home and the statue is stolen by one of the Professor's students, Joe. He removes the protective cloth and conjures up the monkey monster. When Joe, Laphin's daughter Yoyo (Rungnapa "Anny" Brooke, Sherry Ann) and all her friends have a graduation party the beast strikes.