Showtime's  hit series Dexter, about a lovable psychopath, a serial killer who targets only the scummiest of the scum, hits its stride in season 3. Dexter Morgan, played with nuance and glee by the outstanding Michael C. Hall, Dexter is soon back to his compulsion for seeking out criminals who've somehow escaped traditional justice. Hall, one of TV's most talented actors, manages to make Dexter's off-kilter moral compass totally believable, if not quite sympathetic. The rest of the cast is stellar, including Dex's sister, Debra, played by Jennifer Carpenter as the seemingly more combustible Morgan--a hot-tempered Miami detective in the same division where Dexter toils in the background as a blood-spatter specialist. Deb wears her heart on her sleeve, as a cop and a sister, and her deep love for her brother is a key part of what makes Dexter so human. (And Carpenter's chemistry with Hall is amped by the fact that in real life, the actors are married.)

Season 3's breakout guest star is the amazing Jimmy Smits, who plays District Attorney Miguel Prado, a polished pillar of the community, an ambitious politician--and a guy with a secret every bit as dark as Dexter's. As Miguel and Dexter peel away each other's unsavory layers, Dexter tries to tamp down Miguel's blistering desire for revenge, and Miguel begins leading a double life--one that could threaten Dexter's life and family as much as the growing list of bad guys in Miguel's crosshairs. The other main star of Dexter is the city of Miami, its teeming beauty and corruption celebrated in equal measure, and its blistering sun shot without tempering. The city is so integral, visually and viscerally, that it's impossible to think of Dexter being shot anywhere else. The set's best extras--engaging interviews with cast members Hall, Benz, Carpenter, Lauren Vélez (Lt. Maria Laguerta) and David Zayas (Det. Angel Batista)--must be watched on a computer, for reasons that are unclear. Still, the interviews are must-sees for all Dexter fans. It's a killer season.