Lizzie Borden High's class of '72 are going through the motions at their tenth-year reunion, until deranged alum Walter Baylor, driven insane by a sadistic senior-year prank, escapes from the mental institution and crashes the party. When guests start getting bumped off, the other alumni, including snooty yacht salesman Bob Spinnaker, class tease Bunny Packard, and class zero Gary Nash, spring into action to uncover the culprit.