Meanwhile, Splinter takes a serious blow to the head while battling the Mousers in the sewer. Just as the rabid robots are about to make mouse meat out of the Sensei, they mysteriously march off in another direction. Splinter, dazed and nearly unconscious, takes this opportunity to escape by crawling into the tepid waters of the sewer system. The Master is discovered by two human guards, who take him to the TCRI laboratories. At the hi-tech facilities, Splinter discovers that the humans that work there are actually small alien creatures that utilize humanoid robotic bodies to disguise themselves.