Ah the sunny, slim 70s.
Some friends are on a roadtrip, get a flat tire, one goes missing the rest end up at a weird dudes house who has a lot of mannequins.
This is really strange - yeah there's a crazy guy but he seems to have magic powers as well. He could have just been a psycho who likes to dress up (as a mannequin) and make his victims into mannequins, but they've given him powers as well for some reason, not that he really uses them for anything apart from making mannequins dance around.
YES - guy really likes mannequins