The remaining six episodes from the first season of the children's CGI-animated cartoon tracing the origins of the sewer-dwelling, superhero foursome Leonardo, Donatello, Raphael and Michelangelo. The episodes are: 'Karai's Vendetta', 'Pulverizer Returns!', 'Parasitica', 'Operation - Break Out', 'Showdown: Part 1' and 'Showdown: Part 2'.