Tired of always losing to Super Rabbit Boy in their video game world, King Viking goes to the Secret Lands to find the Super Power Up that will give him super powers-- Super Rabbit Boy must stop him, but first he must make it past goblins, ghosts, and other video dangers.

"King Viking decides to find another planet where he can carry out his evil plans without interference, and everyone in Animal Town is delighted; then an alien appeals to Super Rabbit Boy for help and he blasts off to once again confront his enemy--but his level one rocket may not be up to the task." --

Super Rabbit Boy gained his superpowers when, as a baby, he ate the magic carrot he found in the Wise Woods; now King Viking has built a time machine in order to team up with his younger self, Prince Viking, and prevent Baby Rabbit Boy from finding that carrot--so Super Rabbit Boy has to go back in time, and with help from an unexpected player, save his younger self and protect the timeline.

When King Viking, Miss Business, and their henchmen team up to cause trouble, Super Rabbit Boy and Mega Mole Girl also join forces, but will they be able to work together to save Underland?