Once upon a time ... or maybe twice, an underwater paradise called Pepperland, a place where good music always sounds and one lives with joy. However, this well-being is threatened when it falls prey to the Blue Malines, a cruel group that hates music and declares war by sending its army, commanded by the threatening Flying Glove. The band of Pepperland is locked in a bubble from which they can not play while the other inhabitants of the place are paralyzed and turned into blue series. Sent by the mayor to seek help, Fred, a young man from the village, will ride on a yellow submarine and will reach Liverpool. There he will meet the members of the Beatles.