Based on

Movies like Campus Sleuth (1948)

A photographer is murdered just outside a college dance. The body is found by Lee Watson, but promptly disappears, as it's being whisked from one point to another on campus by an ex-con night watchman. However, he isn't the killer, and Freddie, Dodie, Betty and Lee set out to find the culprit who put a big damper on their big event.