The ninja turtles moved quickly across the rooftops of New York, their eyes fixed on their enemy, a female ninja from the Foot Clan who had tried to kill them countless times. This time, she had managed to steal something crucial from them: the retro-mutagen.

The retro-mutagen was an extremely powerful substance created by Donatello, capable of reversing mutations and returning mutants to their human form. If it fell into the wrong hands, it could unleash disaster, or worse, be used against them.

The woman ran as if her life depended on it. Desperate, her breathing was erratic. She stumbled, hitting her jaw on the hard pavement. She got up, ignoring the pain. She ran down some fire escapes until she reached the metal bar, entering through an open window.

She poured the retro-mutagen on a mutant. The effects were fast. Before the astonished eyes of the turtles watching from outside, the creature began to change until it revealed a boy, with black hair and blue eyes, just like hers.

Leonardo was the first to lower his katanas. "I can't believe it..." he muttered.

Michelangelo frowned his non-existent brow sadly. "She just... wanted to save her son."

Raphael clenched his fists, but not in rage, but in frustration for not having seen the truth. "All this time... did we misjudge her?"

Donatello looked at the scene with narrowed eyes. "The retro-mutagen... stole it for himself. Not to destroy us, but to save him."

She sobbed loudly, her tears falling on the boy's face as she kissed him repeatedly. "I did it, my love. I promised you... I promised I would save you" she whispered between sobs, not letting go of her son, clinging to him as if she was afraid of losing him again.

The woman they hated so much was not a villain, but a desperate mother who would do anything to save her son.