In the first part of the two-part season finale, Carter, Dean and Jaimie go undercover to corner two drug-smuggling brothers who use a flower importing business as a cover for their activities. But things go awry when Homeland Security requests that the team keep the smuggling business open so they can trap a potential terrorist. Meanwhile, Dean asks Jaimie out on a proper date; Ty has second thoughts about his impending divorce; and, for Carter - a major life change. Recurring guest stars include MICHELLE BORTH (The Forgotten, Tell Me You Love Me), SEAMUS DEVER (Castle) and JOHNNY MESSNER (Chuck, Cold Case, The O.C.).