Salesman Roy Knable spends all his free time watching television, to the exasperation of his wife, Helen. One day, TV salesman Spike convinces Roy to buy a satellite dish offering 666 channels. The new addition to Roy's home entertainment system sucks him and Helen into Hellvision, a realm run by Spike, who is an emissary of Satan. For 24 hours, the couple must survive devilish parodies of TV programs if they want to return to reality alive.