Michael C. Hall and Julie Benz

When Dexter returns on Sunday, Sept. 27 (9/8c, Showtime), Dexter (Michael C. Hall) is a married man, living in suburbia, with three children. Wait, does that sound like the serial killer we've come to know and love? That's exactly the challenge this season: Can he juggle his favorite pastime and his new responsibilities? To answer that and other burning questions for the fourth season of Dexter, the stars of Showtime's killer series discuss what's to come.

DEXTER (Michael C. Hall)

"We open the first episode in suburbia, with an exclamation point," executive producer Clyde Phillips tells TVGuide.com. "Dexter's worlds collide. I can tell you that's a challenge. Who's more secretive than a serial killer? Now here's a man who is married, three children, a home in suburbia with neighbors all over him, somebody at the station who suspects that all is not right with him. He still has to answer the impulses of the dark passenger that he carries. It is an enormous challenge for him."

Dexter finds an additional challenge with the Trinity Killer, who is definitely not new to the art of murder. "We are so lucky to have John Lithgow, who plays a serial killer, but somebody who has been at it 30 years longer than Dexter," says Phillips. Facing off with the Trinity killer "is a challenge and a learning experience. Dexter has a lot to learn -- well, Dexter thinks he has a lot to learn."

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RITA (Julie Benz)

How does his new bride handle his disappearing acts? "In any relationship you start questioning if someone's disappearing," says Benz. "In the beginning of the season, Rita feels very secure in her relationship with Dexter." Note that she emphasizes in the beginning of the season.

"Dexter is starting to realize that there are a lot of people in his life that he could hurt if his secret is revealed and there's a lot of this creeping-in effect of maybe his loved ones getting closer and closer. If it's ever revealed, we're all going to be devastated," Benz adds.

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DEBRA (Jennifer Carpenter)

Last season, Debra was digging into her father's past, but if she goes any further down the rabbit hole, she'll certainly discover much more about Dexter. "I think what makes Deb the happiest is when her work is going well and she is really expanding and out of the shadow of her father's legendary career, making her work and her life her own," Carpenter tells TVGuide.com. "There's a certain reward that comes with that kind of risk."

Debra's ex, Lundy (Keith Carradine), also returns this season, but Deb already has a new boyfriend. "I don't think the relationship with Lundy ever went away, but the relationship with Anton was certainly comfortable and they both shared a tragedy, so there was a commonality there," she says. "Love always wins. Where's the love? You'll see it in episodes 2, 3 and 4. It goes on and on."

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DET. QUINN (Desmond Harrington)

There's also love in the air for another detective at Miami P.D. "I do have a love interest this year, but not Debra," Harrington tells us. "Her name is Christine, played by Courtney Ford.  She's a reporter, so there are all the things that are difficult about that. I think we're both kind of using each other for our own ends, and pretty simply, sexually." Harrington adds that we'll learn more about Quinn this season: "Some of it's good and some of it's bad."

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WHAT'S TO COME

Instead of waiting until the season finale for a cliff-hanger, the producers are shaking up the show several times this season. In particular, the fourth episode will chill fans to the bone. "We thought of something that would be great for the end of the year and we thought 'screw it, we'll do it now.' Everybody will be talking about it the next day," says Phillips.

"Pretty much every episode has some sort of cliff-hanger that's gripping and you're like, oh f---," adds Benz.

Are you excited for the return of Dexter?