There are a few breeds of "bad movies" out there. This one falls into the "contemptibly incompetent/ nobody here knew how to make a movie. No, that is not hyperbole, these people really had no idea what they were doing. At all." category, the reigning champion of which still seems to be Monster-a-Go-Go (1965), but just by a sasquatch hair.
While Monster-a-Go-Go has its own stunning production history to consider, Curse of Bigfoot is a 1976 repackaged 1958 movie originally titled Teenagers Battle The Thing.
Apparently seeking to cash in on the mid-1970's Bigfoot craze (yes, our younger readers, there was a mid-1970's Bigfoot craze. I don't know. How do any of these things happen? I blame The Six Million Dollar Man and In Search Of, but they seem to post-date this movie, so I have no clue, man. Bigfoot and Wildboy?).
The original film didn't run the correct length of time to be used on TV, and so we're treated to not one, but TWO framing devices for the main story. Luckily, whether director Dave Flocker was in charge of the opening, the original part of the feature, or all of the above, there's a consistent patina of incompetence which shines off every frame.
Fairly clearly the Flocker Bros. (Dave's brother James seems to have been the writer) were influenced by The Thing from Another World (1951) and sought to capture/ recycle some of that movie's magic and plotpoints. In the flashback film, I believe the creature is referred to only as a creature or as a "mummy". Its the framing device which suggests that the creature was Bigfoot, or a Bigfoot, and that the adventure of the film left three students INSANE (and one high school teacher looking nebbishy and maybe like he's ready to star in his own version of Falling Down).
This is the sort of movie where nobody told the director, writer or editors that you don't actually have to show characters walking back and forth, or going to the car for everything, or that you can write around that. It suggests that the best way to kill an ancient mummy/ creature from beyond/ Bigfoot is to stack a few bales of hay to about 5 foot, then put some meat out as a lure, with your weapons of choice being two buckets of gas and flares. The dry hay, I might remind you, is your barrier from the creature.
The good news is that the RiffTrax fellows are in fine form on this episode, and I highly, highly recommend.
You're going to need it, because otherwise the movie is paced like the final hours of a sleep deprivation study, has the characterization of your average Foley's weekend ad insert, and the gripping drama of the telephone book for a city you'll never visit where you don't know anybody (somewhere in Delaware, I'm guessing).