A peaceful weekend of music and art turns sour for Miss Mallard and Willard when a famous masterpiece is stolen. Clues found all over the city point the finger at one suspect: the great Spanish artist, El Ducko. But El Ducko is one of Miss Mallard's dearest friends and she can't believe he is responsible. She takes it upon herself to prove his innocence, retrieve the stolen masterpiece, and capture the real villain, all before the museum closes at six o'clock or as she discovers, it will be too late.