Dexter's struggle to manage his emotions will become a key arc during Season 7 of Showtime's serial killer drama, according to executive producer Sara Colleton.

Late last year, the network signed a deal with star Michael C. Hall and renewed the series for two seasons, each featuring 12 episodes. Season 8 is expected to conclude the show. But before it does, Dexter will attempt to overcome some changeling obstacles to his secret life.

"It is about things he's never experienced before, which are regret, responsibility, shame, betrayal, all of those things," Colleton said in an interview with TV Guide. "Also, it's the flip side of wanting to be known, and then once you are known, there's a loss of freedom.

"It comes with heavy responsibility, so he's dealing with a lot of emotions that he's never had before, and never been allowed to feel before or allowed himself to feel before."

Although the series is set return for two seasons, Season 8 wasn't always in the cards.

"We wanted to end it this year, but the network convinced us that it would be best to do it in two years," Colleton explained. "In some ways, this is a two-season series-ender. We have worked that out and know where it's going to end. Next year will definitely be the last year of 'Dexter.' Absolutely.

"From the very beginning, when I first started developing the pilot, I always knew it would be a seven-year arc for this series. I feel easily that we can be an eight-year show, but I never want it to get old and stale. I want us to go out on a high and everybody on the show is determined to keep the level of it up to the very end. It's always wise to know when it's time to leave the stage before you're asked to leave the stage."

"Dexter" set new rating highs last season -- counting multiple airings, DVR and on-demand viewing -- and pulled in 5.1 million viewers each week.

The series follows a serial killer (Hall) who holds a job as a Miami police forensics specialist while quenching his thirst for the kill by hunting criminals who he believes have escaped justice.

Hall was nominated for four Emmys for "Dexter" and won a 2010 Golden Globe for his performance.

Signed aboard the cast for Season 7 are Jason Gedrick ("Desperate Housewives") as the club manager, Ray Stevenson ("Rome") as a Russian crime syndicate boss and Katia Winter ("NCIS," "Arena") as a Russian stripper at a Miami club.

"Dexter," which premieres Sept. 30, also stars C.S. Lee, James Remar, Desmond Harrington, Lauren Vélez, David Zayas, James Remar.

See more of Colleton's TV Guide interview here.