Mary-Louise Parker, Laura Linney

Showtime finished its 2011-2012 season with nearly 22 million subscribers and 22 Emmy nominations, with five of those in the four leading acting categories. Much of that honor goes to freshman drama Homeland, which is the most-nominated series for the network.

After sneak-previewing trailers for two upcoming series -- Masters of Sex and Ray Donovan -- David Nevins, Showtime's president of entertainment addressed this season's farewells to The Big C and Weeds and teased what's coming up for Dexter and Homeland, both of which will return on Sept. 30.

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Check out the Showtime executive session highlights:

The Big C's final exit: The Laura Linney-led dramedy will conclude with four one-hour installments. "I wouldn't assume anything as how it's going to end," warned Nevins. "They've got an interesting and novel and sort of form-breaking way of where the show's going. It's going to make for a very interesting season."

Weeds gets whacked: After eight seasons, the pot comedy will come to a close in a two-part series finale on Sept. 16. "I've read the final script, and I think it answers a lot of questions very carefully planned towards," Nevins said. As for having star Mary-Louise Parker return to the network, he added, "She's great and can do all sorts of different things, so I would love it. But it's also about us creating a role she'd really want to play. But I think there's a very good possibility to have Mary-Louise on Showtime after Weeds is gone."

Dexter, Season 9? Showtime had intended the serial-killer drama to finish after two more years -- Season 7 and 8 -- but after becoming privy to the "game-changing" plotline coming this fall, the network is considering keeping its options open. "Plans can always change... Deb has to deal with who her brother really is," said Nevins. "Everything changes, so we'll see where that carries us... Every scene is fraught with you wondering, 'What is she going to do? What does he think she's going to do? What does she think he think she's going to do?' They're able to take both Deb and Dexter to unexpected places. [Two seasons], that's the current plan, but I'd be stupid not to leave the door open," for a good idea to keep it going.

A very Brody death? When asked if the Homeland writers would have the chutzpah to possibly kill off its lead, Nevins said, "Anybody can go at any time. Absolutely, it's always a possiblity." He then teased the upcoming season: "I believe we're still on the upswing with Homeland. They made some very bold choices this year. By the end of the second episode, you're like 'Holy sh--!' But the third, you understand what the direction of this season will be."

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What's up with docs: R.J. Cutler's The World According to Dick Cheney and documentaries on Richard Pryor and Suge Knight will premiere sometime next year. Tommy Mottola will also get the doc treatment from filmmaker Brett Ratner. And, at long last, Oliver Stone's 10-part Untold History of the United States will premiere Nov. 12.

Borgias on the border: A fourth season has yet to be ordered, but Nevins assured the critics that the network wants to give producers plenty of time to wrap up the series properly. "We try to make these decisions of when to end a series from a creative point of view."

More Matt LeBlanc possible: "I'm expecting Episodes to come back," said Nevins. "That show is irregular... We tend to be slower to get them on the air."

Ron Howard's Conquest: The newly announced series is still in the "very early stages of development," lacking a script. "I think there's a very interesting show to be done that has genre elements, elements of supernatural and horror, very frightening and gruesome some stuff between these two cultures," said Nevins. "Magic and mysticism are in the core of Spanish Catholics and the Aztecs. He believes it's a period show that hasn't been done before that's "loaded with potential."