TMNT2012: The Pursuit of One's Past

One night, on Christmas Eve, Leo and Raph had an argument. Leo decided to leave before things got physical and ran into Tiger Claw, resulting in Leo being pushed off the roof they were on. Seven years later, in San Francisco, Donnie died in a "lab accident" and his wife, Carol traveled to San Francisco to get mutant PI, John Doe on the case. Unfortunately, the only experience New York gave John was waking up in an alley with the only memory he had of being pushed off a nearby rooftop, and then trying (and failing) to find out who he was. So he wasn't planning to take on the investigation at first, until Carol offered him a quarter million in cash and some insight on his forgotten past. Will John solve the case? Was Donnie's death just an accident after all? What was John's past really? Is he some how connected to to the events of that Christmas Eve? Read to get the answers you seek. Disclaimer: I don't own any version of TMNT or its characters.