An attractive young couple, Nan and Mark, have nothing to do one afternoon, so they go through an old trunk that Nan found in the attic. The trunk contains some very old film, so they take a look. And another look! The old film is a series of rare, classic 8mm stag films (blown up to 35mm and tinted blue, in the theatrical version.) The films are very funny, and presented with appropriate comments from Nan and Mark, who watch along with the audience. Some of the films are from the 30s, some from the 40s; a few will be remembered fondly from college stags, but many are from private collections, not seen since their initial distribution. The action switches from Nan and Mark, who are becoming very aroused by the films, to the films themselves. Finally, the young couple can wait no more, and they climb the stairs to the bedroom, where they will act out a stag film of their own.