Bowser, with the aid of the Broodals, a family of anthropomorphic rabbits serving as his wedding planners, kidnaps Princess Peach from the Mushroom Kingdom and takes her aboard his airship, intent on forcibly marrying her. Mario attempts to rescue her but is thrown off the ship by Bowser’s top hat and falls into the neighboring Cap Kingdom. With Mario gone, Bowser stomps on Mario’s cap and begins his wedding to marry Peach. Bowser leaves Mario’s cap to drift into the ship’s rear propellers, shredding it to pieces. A piece of the hat is grabbed by Cappy. Mario meets Cappy, one of the Cap Kingdom’s sentient hat-like creatures, and learns that Bowser also kidnapped Cappy’s sister Tiara to be used as Peach’s wedding tiara. Cappy joins Mario and takes the shape of Mario’s cap, providing him with the ability to temporarily capture other creatures and objects. They travel to the nearby Cascade Kingdom and recover an airship, the Odyssey, and begin pursuing Bowser.