Donatello experiments with mutagen in an attempt to find a cure for April's mutated father. But one of his expirements goes wrong and he is unleashed in the city.

Mikey struggles to convince the others that a new mutant is trying to attack and capture people using living pizzas.

Ein genervter Mikey läuft weg und freundet sich im Wald mit einem Mutanten-Frosch an, dessen Gang plant, die Welt der Menschen anzugreifen, was Mickey natürlich verhindern will.

Michelangelo and Casey become friends with Mondo Gecko, a radical, skateboarding, reptilian teenager.

The Turtles must gain the trust of the Utrom Council in order to find the next piece of the black hole generator.

Raphael must overcome his fear of insects to lead the team when they are forced to battle Stockman-Fly's new insect minions.

When the Turtles and Renet return to a present-day New York City infested by an undead army of monsters, they realize they may have made the situation even worse.