It's the kings' birthday and for their royal present, they each get one wish that will come true. Right before blowing out the candles, Boomer learns that Brady has been bragging to the entire island that he is the older twin. Boomer uses his wish to find out the truth about who was born first, while Brady's wish is that Mikayla compliments him all day. Boomer travels to the center of Mt. Spew to meet with the volcano's Oracle and learn who is the older king, but the younger brother will no longer be co-king if it is known who the older brother is. So Brady, Mikayla, and Mason chase after Boomer.

Boomer and Brady discover Vault 14, a secret vault which protects Kinkow's most mysterious and powerful artifacts. They find the Duplicatus Plantus, a plant that copies anything it touches and make clone of themselves. The clones fill in for Brady and Boomer so that they can go surfing, However, clones want to replace Brady and Boomer forever.

Brady and Boomer head back to their high school prom in Chicago to flaunt their royal status. Boomer chooses a girl named Rebecca, who he thinks he once had a date with and Brady chooses Mikayla.

Brady and Boomer are just two ordinary twins. Or, so they thought. They soon learn that their parents were king and queen of a small island and they are next in line to rule. But, their distant cousin is planning to stop them from being kings.

The twins must save their island from an erupting volcano that they awakened. To do this they must cross into the dark side of the island and find a replacement rudy which is a task impossible to do. Lanny tells the villagers that Brady and Boomer are dead so he can become the next king.

Brady and Boomer try to recover a lost medallion that is sacred to the island but Brady, along with Mikayla, is kidnapped by the Tarantula people. Meanwhile, Lanny embarrasses Mason by showing an old workout video that features him in it.

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 must perform for the islanders at the Annual Harvest Festival, and Boomer can't wait to show off his singing skills. Brady knows Boomer has a horrible voice, but doesn't have the heart to tell him. When Brady's plan to protect his brother from humiliation backfires, Boomer discovers Brady is a terrific singer and arranges for Brady to sing to the kingdom.

After watching a scary movie, Brady thinks the castle is haunted. When Lanny takes him to a evil arts woman to prove to Boomer the castle is actually haunted, he brings back a ghost but not the one he intended.

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

Boomer and Brady meet an odd creature in the woods named Ogie (Doug Brochu). But Brady is jelous of the Ogie and is mean to him. Brady fills a void by being Lanny's friend, but Lanny's plot is to kill him. But when Boomer is invited to a feast, he isn't going to a dinner; he is dinner—or so it seems.

Boomer and Brady join the Kinkow Fight School

The kings try to boost thier approval ratings.

The twins must save thier island from an errupting Volcano that they awakened. To do this they must cross into the dark side of the island and find a replacement rudy which is a task imposible to do. Lanny tells the villagers that Brady and Boomer are dead so he can become the next king.

Brady and Boomer find a cute creature in the jungle and decide to keep it as a pet. But, it isn't cute for long

A pirate gives Boomer and Brady a riddle to solve that supposedly will lead them to a magical coin but the puzzle is actually a trap to ensnare the brothers so the pirate can steal the royal treasure.

Brady and Boomer want to join the Riptides, a gang famous for pulling pranks all over the island. Their final test before they will be accepted into the gang is stealing Yamakoshi; Lanny's pet fish.

Brady gets jealous when Mikayla introduces her friend, a boy named Tristan. To impress her and make sure Tristan does not win her over, he gets Boomer to go to school with him and he tries to do everything he can to keep Mikayla and Tristan apart.

The boys learn about Junga Ball, a dangerous game much like basketball. when they are told they will be team captains they decide to take the offer. But, Brady becomes too bossy and Boomer creates his own team.

Feeling homesick, Boomer and Brady call Aunt Nancy and Uncle Bill to check in, but accidentally end up scaring them with their tales of Tarantula people, quick sand and giant bugs. While Aunt Nancy and Uncle Bill rush to the island to bring the twins back to Chicago, Brady is accidently stung by a dangerous Waka Waka bug. With the help of Mason and Mikayla, the kings must hide Brady's strange side effects including pumpkin head and amnesia in order to prove that the island is safe enough for the kings to stay and rule. Meanwhile, Mason has a date with a girl named Stewy.

Brady and Boomer find a cute creature in the jungle and decide to keep it as a pet.