NCIS: Naval Criminal Investigative Service is that rare TV series that grows more popular over multiple seasons. The ratings of this slick and skillful crime show’s sixth season topped the previous five--no doubt due to blending a satisfying story formula with a perfectly balanced cast. Special Agent Jethro Gibbs (Mark Harmon, whose long career includes St. Elsewhere and Chicago Hope) is the stern but caring father-figure to a squad of younger agents, including obnoxious, self-satisfied field agent Tony DiNozzo (Michael Weatherly), sexy ex-Mossad agent Ziva David (Cote de Pablo), quizzical cyber-expert Tim McGee (Sean Murray), goth-chick forensics whiz Abby Sciuto (Pauley Perrette), and crusty but wise medical examiner Donald “Ducky” Mallard (David McCallum, whose career goes back even farther than Harmon’s, to The Man from U.N.C.L.E.). The banter and tensions of this eccentric sextet provide a reliable comic foil to the frequently gruesome events under investigation.

At the end of the fifth season, this crack team was scattered to the far corners of the earth by NCIS Director Vance (Rocky Carroll), leaving Gibbs with a green new crew--but within minutes of this season’s first episode, that’s revealed to be a ruse: Someone in the new team is sending secrets to the enemy. Naturally, sussing out the traitor requires pulling in the old gang one by one. From there, the season gallops along with gripping and often gory opening scenarios (A shower sprays blood! A disembowelled Navy captain has a pentagram on his back! A dying marine writes a number in his own blood--and it’s the number for Gibbs’ service record!) which are cleverly twisted to reveal even more sensational conclusions. The best episodes mislead the viewer multiple times before finally unveiling a surprise solution in the last few minutes. Gliding under these tangled threads are comic subplots about stolen cupcakes and cyberdating. Harmon anchors the show with understated gravitas (sometimes he doesn’t change expression through the entire episode), but the quirky side-players provide the juice, particularly old hand McCallum and the petulant but demanding Perrette. Though the NCIS setting means the crimes need to involve Naval personnel, that’s just window dressing--this is a show that any fan of detective procedurals will enjoy. NCIS: The Sixth Season features plenty of extras for fans, including commentaries that show the actors have the same chatty chemistry as their characters. --Bret Fetzer

Stills from NCIS: Season 6 (Click for larger image)