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.

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.

While trying to prove that they are the Kings of Legend, Boomer and Brady accidentally bring Zadoc, an ancient evil statue, to life, consequently putting the entire island in extreme danger. The twins cede the throne to Lanny for the better of Kinkow and depart on a balloon voyage back to Chicago for good, until the balloon catches a wind and sends them plummeting straight to the Dark Side of the island.

Zadoc's minions capture Lanny and try to squish him with a huge rock. Lanny hands the throne back to Boomer and Brady. Mason goes after Zadoc and sees Boomer and Brady fight and defeat Zadoc and realizes that maybe they are the kings of legend.

Boomer falls in love with a new girl, but the girl claims to be made out of Ice. Meanwhile, Lanny sends a servant to find Mason and Mikalya.

Boomer goes to Chicago in an effort to convince Rebecca's father to let him see her after he forbids them to be together. Boz tags along and searches for a safe place to hide the Bat Medallion. Meanwhile, a menace from the past launches a surprise attack on the kings and it is revealed that Rebecca's father used to be part of the Tarantula tribe. As a result, he erases Rebecca's memory of her relationship with Boomer to keep her safe.