The earliest memory Jane has is waking up naked in the middle of a dirty Chicago alleyway with absolutely no memory of who she was or where she was from. Or why her skin was green. Staggering around in a confused haze, she was attacked by some nearby bums with less than noble intentions. Much to their, and her own, surprise she as able to easily take them down and stole one of their coats to cover herself after the fight.
Making her way to the nearest police station, she walked in and reported herself as a missing person. Although more then willing to help the police had no idea where to start given the woman's odd skin color other than thinking she was somehow related to the city's resident superhero Martian Girl. When the two did meet, Martian Girl probed her mind and found that the woman's memories weren't blocked they were gone. As if they had been ripped away from her mind.
Feeling more lost than ever the woman had no choice but to rely on the kindness of Detective Eva Miller who helped her get in contact with Martian Girl in the first place and offered to let her stay with her until she could get back on her feet. Being that the first thing she needed was a name she decided to take on the rather snarky moniker of "Jane Green" that one of the other officers had given her.
Once she WAS back on her feet, at least partially, Jane decided the best route for her to take was to enroll in the Police Academy and join the force so she could look into her background first hand while also repay Eva as much as she could for her kindness.
The weeks in the Academy passed quickly and surprisingly easily for Jane. As she ran throw the training she felt these strange senses of Deja Vu as if she had done the exercises before or at least something similar to them. It was also in the academy where she found out she had an incredible healing facter after a particularly nasty spill she took during the obsticle course. Through her own series of experiments she found out that not only would her wounds close almost instantly but she could also regrow severed limbs.
Naturally these unique talents helped her pass through the academy with flying colors and soon enough she was on the streets as a beat cop with her new partner Nash Wilson. Now she does her best to keep the streets safe while still trying to uncover the mysteries of her own life.