It's the kings' birthday and the whole island is celebrating. When Boomer learns that Brady has been bragging to the entire island that he is the older twin, Boomer heads out to the belly of Mt. Spew to ask the volcano's Oracle which king was born first.

Brady and Boomer discover Vault 14, a secret vault deep inside their regular vault, which protects the islands' most phenomenal objects. They discover a Duplicatus Plantus, or ditto plant, and the Kings clone themselves.

When Brady and Boomer learn their dad was the best warrior in island history, they want to be more like him, so they attend Kinkow Fight School. But when instructor Mason favors the Kings, jealousy overcomes his previously prized pupil Mikayla.

When the Kings discover their biggest fan is a boy named Hilo, they regale him with greatly exaggerated stories of their heroism. But when Hilo takes off to emulate their heroic deeds, the boys are forced to rescue him with skills they do not possess.

When the king of the neighboring island of Cornea makes a peace offering in the form of an arranged girlfriend for either Boomer or Brady, the kings agree to battle in a "Third Wheel Duel" competition for the gorgeous potential royal girlfriend.

After watching a scary movie, Brady sets out to prove that the castle is haunted. He conducts a series of tests and later presents the "indisputable evidence" to his staff.

When Boomer and Brady become homesick they dial up their Aunt Nancy and Uncle Bill via the "Wi-Fi" tree, but end up scaring them with their tales of Tarantula people, quick sand, and giant bugs.

It's time for the annual "Harvest Festival", and much to Boomer's and Brady's surprise, they must entertain the island populace with song. Boomer can't wait to show off his skills, but Brady is reluctant because Boomer is a terrible singer.

When Boomer and Brady learn that their high school back in Chicago has not heard about their recent crowning, they take an ill-advised trip back to the windy city to show their high school peers how awesome they are now.

Brady and Boomer decide that their island needs some fun, so they decide to pull pranks on everyone. No one likes their pranks, but the kings fear that bad karma is coming their way. Meanwhile, Mason gets addicted to a video game.

The kings learn about an exclusive club of rebellious prank-pulling punks called "the Riptides" which is off limits to Kinkow royalty. As the kings of trouble, Boomer and Brady immediately want to join the club.

The unscrupulous pirate Two Peg gives Boomer and Brady a mysterious riddle, that if answered, will lead them to a magical coin that will grant their utmost desire. Despite Mason and Mikayla dismissing it as hogwash, Brady and Boomer go to find it.

After a series of mummy nightmares, Boomer and Brady realize that they put the entire island in great jeopardy when they lost the sacred bat medallion. The kings head into the jungle to retrieve it from the mummy's possession.

Boomer and Brady learn the traditional game of Junga Ball and begin to practice for The Junga Ball Cup, in which they compete against the neighboring island of Kipi Kipi. When Brady benches Boomer during practice, Boomer quits to form his own team.

Brady gets jealous when Boomer strikes up a friendship with Oogie, a member of the highly unusual Flaji island clan. After Boomer is invited to join Oogie in a special Royal Feast, Brady learns that the Flaji were once rumored to be cannibals.

When Boomer and Brady realize that their royal privilege doesn't excuse them from having to go to school, they find themselves back in the classroom, where Brady discovers major competition for Mikayla's affection.

The twins discover a cute little animal and decide to make him their pet. Unbeknownst to the boys, their pet, Pupaley, grows into a towering behemoth when angered. When the boys try to return him to the wild, he grows and makes they boys HIS pets.

While Mason is out of town, the twins hang out with a bunch of mermaids and Mikayla turns into one herself.

Hibachi, the best (and shortest) surfer on Shredder Beach bans Boomer and Brady from the beach after they tick him off. When efforts at befriending Hibachi fail, the boys end up challenging him to a Surf-Off, forgetting that they don't know how to surf.

Twin brothers Boomer and Brady's lives change forever when a warrior visits their school. They find they are joint kings of the remote island of Kinkow.

When the Royal Secretary of the Island of Kinkou arrives to inform fraternal twins Brady and Boomer of their royal lineage, their lives change drastically. Now, the boys must relocate and claim the throne as joint Kings of the island.