One of those (Japanese) series that is unbeleivable but keeps you watching because the cast carries it. Initially very good but degenerates into a morass of (series) tropes [the nasty gangster who stops being nasty, the ethical will triumph in the end etc.], unbeleivability and plain silliness....but you keep watching 'cos the cast is trying hard and you remember that excellent start and (vainly) hope fot its return.