4K Ultra HD is 4 times sharper than HD. HDR (High Dynamic Range) provides brilliant brights and deepest darks, and a wider colour spectrum adds more lifelike colours for the ultimate movie watching experience. Also includes Blu-ray disc and Digital Download to watch anywhere on all your devices.The turtles return to face a new challenge when Shredder escapes from custody and joins forces with Baxter Stockman, a mad scientist who plans to use a serum to take over the world. Along for the ride are Bebop and Rocksteady, two dim-witted henchmen who provide plenty of muscle. Luckily, the turtles have their own allies in April O'Neil, Vernon Fenwick and Casey Jones, a hockey-masked vigilante. As the pizza-loving heroes prepare for battle, the notorious Krang also emerges to pose an even greater threat.