This feisty little Canadian slasher from director Paul Lynch may not hit as many marks as Prom Night, but it sure as hell manages to have some fun in the process.

A group of six people end up stranded on the notorious Dog Island. Why is it notorious? Because the isle is reputedly inhabited by a reclusive, withdrawn heiress and her savage guard dogs and no one has ventured there in decades.

Unfortunately, there is also a hulking, mutant killer on the island. Can you guess what happens next?

One by one, the uninvited guests get picked off by the humongous madman. Will any of them escape with their lives before it's too late?

The island setting and teen cast hearken back to the UK thriller Horror on Snape Island (1972) aka Tower of Evil.

Still, although it's murky and derivative, Humongous conjures up a life all on its own making.

The flashback opening to Labor Day Weekend 1946 is ambitious and does The Prowler proud; it does a nice job of setting the backstory for the mysterious Ida Parsons who may or may not have given birth to a psychotic aberration who may or may not terrorize any unwitting visitors to Dog Island in decades to come.

The cast is oddly likable, from the genuinely sweet, hunky protagonist Eric (David Wallace), to his underused sister Janit Baldwin (from Ruby) to his obligatory jerk-jock brother John Wildman. And of course, there's Eric's pretty girlfriend Sandy (Julian, the final girl here).

There are some minor splashes of gore, but it's all rather conservative. Instead, we're treated to a few quick kills and some bargain basement psychology ripped from Friday the 13th Part 2's climax. There's also a moody score from Terror Train composer John Mills Cockell.

Also known as Dog Island.

See also Joe D'Amato's 1980 Antropophagus, containing more or less the same premise but littered with entrail-eating, fetus-gorging and the like.