Synopsis

The Teenage Mutant Ninja Turtles are stoked when Professor McGuffin sends them on a special expedition to the ocean floor where the heroes are shell-shocked to discover TURTLANTIS, a subaqueous civilization that reveres turtles! But not all is as it seems under the sea...and when the fearsome fighters find themselves conscripted into a gladiatorial arena, they'll have to do battle against a familiar foe to get back to the surface...

Plot

The Teenage Mutant Ninja Turtles agree to help Professor McGruffin find his lost deep-sea probe as a way to make up for breaking into TCRI labs while under the mind control of The Rat King.

The turtles take one of McGruffin's sub and are soon attacked by a mechanical squid that takes the turtles to an undersea city. There they meet King Lodrom and Queen Kallista, the leaders of Turtlantis, of a race that evolved from turtles. The King and Queen offer to give the turtles back the probe, if they will battle "the Champion" in their arena, a deal the turtles quickly agree to, assuming the four of them can take on one champion.

In the arena the turtles discover the champion is Slash and they are out matched, but Donatello gets an idea. He asks the King to flood the city, and this will make Slash want to leave, while the citizens will be fine. The plan works and the turtles make their escape and Slash grows bored.