Two fraternal twins, Brady and Boomer Parker live in Chicago with their aunt and uncle until they are told by a royal advisor, Mason that they are kings of their own island known as Kinkow. As the brother's parents were king and queen of the island until they died. Brady and Boomer will now rule the island together. As the two wreck havoc around the dangerous island as they must find a way to solve it the help of Mason's daughter, Mikayla. Meanwhile, the brothers' cousin, Lanny tries to get rid of the kings, but his plans don't work.
Brady leaves the island because he believes that Mikayla won't go out with him because he's too immature. Brady goes back to Chicago because he wants to be mature and do some growing up, but he can't do it on Kinkow. Boomer wants to go after him but a storm keeps him from going. Once the storm clears up, they find a boat that was washed up on the island from the island of Mindu. Their king, Boz has the Kinkow swirl birthmark on his bellybutton. Mason and Timothy Kalooka-Khan reveal that Boz is Brady and Boomer's long lost brother. He got lost in a storm and was never found. Their parents were devastated and they passed a law that no one was to speak of Boz ever again. As Boomer gets over the fact he has another brother, he lets Boz rule Kinkow with him.