Sensei. Master. Mutant. Rival. Rat-dad. Of all his many roles, Splinter has most cherished being a father. When his mutant ninja turtle sons grow into the Teenage Mutant Ninja Turtles, they seek a world beyond the sewer home Splinter has built for them. With his training, and some last-minute parenting advice, the Turtles fight to keep their city safe. Now it's just up to Splinter to keep them safe, too.