I've pulled most of the story details from the 2012 TV show, but sometimes I include other universes, too. All constructive feedback is welcome and appreciated.

PART I:

THE SHREDDER GAZED OUT AT THE NIGHT—the tall skyscrapers blotted out the few shining stars that lined the dark sky in the city. Shredder stood on an outstretched balcony listening to the sounds; it was a still and quiet evening. There was only an occasional car honk, music, or loud voice from a pedestrian to disturb the silence. New York was safer than it had ever been. The Foot Clan now had total control—Shredder oversaw many aspects of the city's security.

It was a battle hard won and not without its sacrifices. Shredder thought about the losses every day and wondered if it was worth it. Even now, under shining armor, Shredder fingered the long scar that stretched from collarbone to earlobe. The slice had almost killed Shredder. In the room at Shredder's back, Foot soldiers trained with Sensei. Their movements were precise, silent, and extremely effective in real life situations.

"Time passes slowly," Shredder whispered almost reverently, as if words would disturb the stillness of the city, the night, and training.

Renet pulled away from the railing that overlooked the dojo. She held her tall staff in one hand—the top resembled a lantern and glowed faintly. "You will be reunited with him. We don't have to wait anymore."

"How much longer?"

Renet sighed and moved towards Shredder. She didn't wear her helmet and her blonde hair rested passed her shoulders now. Three months. They'd been waiting already for three months. The ache was still too new to Shredder. But Renet felt the same loss. So did Sensei—it was even stronger within him. "We can put the plan in motion. They'll need our help with the Kraang. They can't do it alone."

Shredder knew it was inevitable that they had to cross into the other universe. Renet had seen it. As a timestress, Renet had the ability to move freely from universe to universe, no matter what time. Shredder could not. Renet couldn't change the past, no matter how she tried.

And she had. The first month after losing their friends, Renet had gone back and disrupted the past, almost destroying the future.

"Do it," Shredder told Renet, finally turning to look at the woman. Shredder was slightly taller than Renet and had eyes as black as the night sky they stood under. Sometimes, Renet was unnerved by those eyes. They were haunted, unhappy, and empty. Renet knew she had to do something soon—Shredder needed her help more than ever.

Renet only nodded, too exhilarated to speak. They'd practiced every scenario. Renet knew the plan inside and out. Her helmet materialized on her head. The twin glass globes where her ears were shimmered brightly. Renet lifted her staff before Shredder could argue, then tapped it lightly on the ground. Renet disappeared.

Shredder was left alone once again to dwell on the darkness. The haunted expression in Shredder's black eyes were all Renet could think of as she passed through the portal and into the void between worlds.