How did this only go for 2 seasons? Complex interrelationships with no clear good guys and bad guys and no obvious path or easily resolved outcomes. Substitutes the kind of dark menace of 'the Wire' with a set of situational dilemmas that have the key players trapped in their circumstances. At the same time, manages to keep a dazzling pace up so doesn't lumber along like many police shows and the balance of time between the bad guys and the not so bad guys is very interesting. Excellent.