Once Upon a Mattress is a satirical fairy-tale. In a medieval kingdom, the domineering Queen rules while the King is cursed silent. The Queen bans all marriages until her son, the Prince, weds a "true princess" via her impossible sensitivity tests. Swamp princess Winnifred the Woebegone arrives boldly, swims the moat, and charms the Prince. Despite the Queen's schemes, including stacking 20 mattresses over a pea, Winnifred passes the test. The story is presented through lively songs and hilarious chaos, making for a memorable evening full of laughs.