S5·E3 Legend of the 5 Dragons

The Turtles train with the Ninja Tribunal to prevent the resurrection of the Shredder. But when Splinter and the Ancient One express serious doubts about trusting the Tribunal, the Turtles are confused. If they all agree on the goal, why the doubts? To explain the danger to the Turtles, Splinter and the Ancient One reveal the secret history of the Tribunal… including the true origin of the Shredder!