Since it's second season, Dexter has struggled more and more each year to retain believability and quality. In season six, as the sympathetic serial killer contemplates the value and purpose of religion, it finally plunges into the deep end of head-smacking ridiculousness.
While Dexter concluded last year with a bit of melancholy, having had let go of a woman he thought could be his soulmate, he's surprisingly chipper when we meet up with him again. A year has gone by in Miami, bringing with it only a few changes and all of them having to with the supporting characters. Angel and LaGuerta are no longer married. The former is now Dexter's next door neighbor, living there with his attractive younger sister (Aimee Garcia), Harrison's new nanny. LaGuerta, meanwhile, has wormed her way up the chain and has been promoted to Captain, leaving the homicide department in search of a new leader. Other than searching for his latest victim and making a comic visit to high school reunion, Dexter's main focus is finding a preschool for his son. After visiting the Catholic school that Angel's daughter attended and begin quizzed on his faith, he begins to contemplate the subject of faith and whether introducing religion into Harrison's life may offset any of the damage brought on by having a murderer for a father.
Faith and religion are sticky subjects and while Dexter's reasoning for exploring a higher power makes sense, it's a theme that would be better served by a more subtle hand than the Dexter writers have ever been capable of wielding. This becomes more evident as the series's guest stars are introduced. Dexter's big bads are usually one of the strongest elements of any given season, but the dysfunctional serial killing team of Edward James Olmos and Colin Hanks—themselves a pair of religious zealots—aren't nearly as interesting as the corpses they leave behind. Mos Def fares better as an ex-con who claims to found God in prison, a story that leaves Dexter unconvinced. It's not the fault of the actors that their stories don't work, it's that they're used to drive the religious themes of the season into the viewer's head with the subtlety of a sledgehammer to the skull. The most compelling part of the first three episodes involves Deb further venturing into adulthood and when of the show's most reviled characters is the season's high point, there's clearly a problem.
Season six of Dexter premieres 8pm on Showtime.