Magician's assistant Corky performs disastrously at his first solo appearance. He is given a ventriloquist dummy called Fats to improve his act and within a few years Corky is at the height of fame. However, Fats has developed a mind of his own and wants to control his master.
A lonely boy becomes good friends with Ben, a rat. This rat is also the leader of a pack of vicious killer rats, killing lots of people.