When a pretty Wren faints in a crowded train, Private Bud Flanagan and Captain Ches Allen are quick to render first aid. But over Bud's head, a heavy kitbag wobbles; it falls and scores a direct hit, knocking him unconscious. What follows is a dream sequence involving Ches, the Wren and Bud himself in a series of hilarious adventures as well as a magical medley of the duo's best-loved musical numbers!