Once Upon a Mattress is the hilarious musical-comedy version of The Princess and the Pea that shot actress/comedienne Carol Burnett to stardom. Prince Dauntless' possessive mother won't let anyone in the kingdom marry until the Prince does; yet she disqualified with impossible tests every young princess who tries to win the prince. When the hardy Princess Winnifred of the swamps swims the moat to win her man, the lords and ladies do their utmost to help her pass the queen's test of delicacy: detecting a pea hidden under a stack of mattresses.