It had been two weeks since the accident, and Mikey was still unconscious. His brothers are still worried about their little brother. Donnie stayed in his lab most of the time to find out what was inside the chemical. Until he found something.

"Guys! I found something!" He shouted. Leo and Raph sprinted to Donnie's lab. Once they were inside, Donnie explained what he found in the chemical.

"I analyzed everything that was contained in the substance, and I apparently found traces of mutagen inside." Raph and Leo stared at Donnie, in shock. Leo was the first one to speak again.

"So Mikey's been double mutated?" He asked. Donnie nodded, "The Kraang must be trying to create a new kind of mutagen." Then they heard a crash in Mikey's room. Afraid for their brother, they sprinted to his room,opened the door and were shocked at what they saw. A flame colored mutant tom cat, with baby blue eyes, laying on the floor, dazed. He sat up and spoke to the tree turtles.

"Wow, what happened?" He asked. Mikey? Turtles just stared at the cat and, finally, Raph spoke.

"M-Mikey?" He rasped, "Is that you?" The cat looked up at him.

"Yeah, who do you think it is?" Then be noticed the change in their height, "And why am I way shorter than you, than usual?" He meowed. He looked in his full body mirror and screeched, "What the heck? I'm a cat!" He yowled and ran out of the room. The brothers chased after him and tried to catch him, but failed. Mikey spun around and yowled.

"Get away from me! I'm useless as a ninja, now!" He shouted, he ran into the sewers. Master Splinter emerged from his room, "What is going on in here!?" He demanded. The three brothers stared at him, surprised by his inconvenient arrival. They looked at each other, thinking about who is going to tell him. Finally, Donnie spoke up.

"W-Well, sensei, um, funny story, uh, y-you see, Mikey is um, a cat." He stuttered. Master Splinter widened his eyes in disbelief, he twitched his whiskers. He sighed.

"You three must find him and bring him home." He ordered.

"But how are we supposed to catch a lightening fast mutant cat in a big city?" Raph protested. Leo and Donnie nodded in agreement. 

"We'll have to wait, there is a chance that he would return." Master Splinter decided. The three brothers wanted to protest but they remembered Mikey's expression when he realized that he was a cat now. If they went looking for him, he might run away if he saw them. They decided to wait for his return.