xclusive: Bloody good 'Dexter' spoilers!

Apologies in advance for perpetuating an overused pun, but Dexter's fourth season sounds, well, killer.

When the Showtime hit returns next fall, six months will have lapsed on screen, leaving newlyweds Dexter (Michael C. Hall) and Rita (Julie Benz) the proud parents of a baby boy. "This season, we're going to deal with: Can a serial killer juggle a personal life, work, and his 'dark passenger'?" reveals executive producer Sara Colleton. "In other words, can Dexter have it all? Which is something all of us grapple with every day of our lives. So we're taking something that is a very human dilemma and putting it through the prism of Dexter's special needs."

Further complicating Dexter's intricate balancing act will be a new, as-yet-uncast male antagonist who will "cross paths with Dexter in a major, dramatic way," teases Colleton. "He will illuminate a lot about Dexter's life and force him to make some tough choices." (Word is they're looking for a "Jeff Daniels-type" to play the role.)

Meanwhile, Dex's plucky sister, Deb (played by Hall's real-life wife, Jennifer Carpenter), will unwittingly threaten to shed light on his dark secret. "All the way through the season, Deb -- in her need to know her father more -- is going to get closer and closer to figuring out who Dexter's mother was and her relationship with her father," says Colleton. So might the day come when Dex is forced to slice and dice her? "That is inconceivable to me," declares Colleton. "Deb and Dexter are the best brother-and-sister team ever." One could even call them...killer. (Sorry again!)