When Will accidentally creates a portal during a trip to the zoo, he is thrust into an incredible adventure.

Joined by his friends, Riya and Sam, Will travels to the Endless Ocean to investigate some recent Void sightings. On Zebra Beach, they meet a sea lion who loves riddles and has some magical fish to help them breathe underwater.

Will and his friends take an underwater train to the legendary Coral Circus, where they meet many strange aquatic animals. However, when a Nulth BORE shows up, it becomes apparent that their journey into this underwater world is only just beginning!