Nellie Andreeva

With Dexter headed into Season 8 and Californication into Season 6, attention understandably is focused on Showtime’s plans for ending the two series. Both series have found a second wind, hitting some of their best ratings in their most recent seasons. The two-year pickup of Dexter for Seasons 7 and 8 was unofficially billed as the serial killer drama’s final act. But, at Showtime’s TCA session today, Showtime entertainment president David Nevins stopped short of committing to an end date for the show. “We’re not making any announcements today about when Dexter will end,” he said, adding, “I think I will clarify before Dexter goes on this season (in June). We have clear end game in place,  I can’t talk about it just yet.” Just how important Dexter has been to Showtime? “Dexter to Showtime is what Batman is to Warner Bros., it is a cornerstone franchise,” Nevins said.

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Having a set end point is not as critical for Dexter‘s companion Homeland, Nevins said. “It is a show that is incredibly changeable if you haven’t noticed,” he said. “I think it’s got a really long life, it is on the rise, like Dexter.” While he admitted that he agrees with some of the criticism about the recent second season, Nevins said he personally liked it. “It started really strong and ended really strong,” he said. Speaking of Homeland‘s Season 2 ending, Nevins would not confirm whether star Damian Lewis will be back as a series regular next season.

On Californication, whose sixth season premieres tomorrow night, “we’ll make a decision about another season I think fairly quickly into this run,” Nevins said. “It’s a decision on year by year, season by season basis.”

Overall, giving series proper ending is “really important to me,” Nevins said. “It’s really important to me that our audience feels taken care of.” That is why Showtime decided to bring Big C as a limited series, he said.

Other notes from Showtime’s session:

– David Nevins on passing on Under The Dome, which has since been picked up to series by broadcast sibling CBS: “I really liked the script for Under the Dome but it always felt fundamentally not us and more network,” he said. “I tried at one point to push it, but I felt I was pushing it out of what it was meant to be. But I actually facilitated helping get the script to (CBS’) Nina (Tassler), and I think it’s found a really good home. I think it’s gonna be a really good show…I think it’s going be better in a broadcast environment than it would be on pay-cable.”

– Matt Damon will guest star in Season 2 of House of Lies, which premieres Sunday. “He stars as himself,” Nevins said. “He comes to those guys trying to figure out how he can get a charitable organization so he can compete better with (George) Clooney.”

Episodes’ third season will premiere in early 2014 because creators David Crane and Jeffrey Klarik, who write every episode, have full creative freedom and scheduling flexibility. It will be “fairly split between London and Los Angeles.”

TV Editor Nellie Andreeva - tip her here.