The Hamato brothers Leonardo, Raphael and Michelangelo and Raph's young student Renoir are settling into their new life together in Raph's sewer lair. Leo expresses his esteem for Raph in having tried to keep the family together as well as he did even after Leo had abandoned them. Leo also formally introduces himself to Renoir, asking the student to evaluate Raph as a sensei. Mikey returns from Donatello's lab with a new Shell Cell for Leo, having gleaned nothing from Donnie except for how bizarre their reclusive brother has become. Leo observes how Mikey does not seem to have matured in 17 years, only to be told that Mikey had actually hyper-matured during those years and only reclaimed his own ways the day before. When Leo is finally alone, he uses a hidden communication device to contac