Yuuto Lenix, a former DEA investigator, was arrested and received a life inprison for the murder of his partner, which he claims he didn't commit and wasframed for the murder. While serving his sentence, an FBI agent offers him adeal to look for a particular criminal hiding in the same prison. If hesuccessfully delivers what the FBI is searching for, then Lenix will go homefree. He accepts this "under cover" assignment, hoping to be set free.