Beneath the human community, lies centuries secret of the complex wolf/werewolf community. When Kai, a teenage wolf failed his crucial third trail and was condemned for execution, he fled into human society to seek refuge. By twist of fate he encountered D.O, a werewolf hunter with a problem of his own. Together they formed an unlikely bond and teamed up to investigate the recent grisly murders in the city as well as to solve the mystery behind Kai's failure in his third trail.