Ashton Kutcher, Jon Cryer Ashton Kutcher, Jon Cryer

Two and a Half Men has never been shy about pushing the envelope, and that won't change this fall.

Speaking to reporters after her executive session at the Television Critics Association fall previews, CBS Entertainment Chairman Nina Tassler revealed the final-season plan, which includes a fake gay relationship between Walden (Ashton Kutcher) and Alan (Jon Cryer) — and a new half man (or woman)!

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"Walden is going to have a major health scare and it is going to give him a little bit of an existential crisis," Tassler said. "He wants to find a way to add more meaning to his life, so he decides he wants to adopt a child. In doing so, he starts the process and he realizes that it's very difficult, to adopt a child as a single, straight man. So, once and for all, he decides, 'I'm going to propose to Alan, we're going to get married and adopt a child as a gay couple.'"'When asked if the LGBT community might cry foul, Tassler demurred. "It's a very positive statement," she said. "It's like, 'I am going to adopt a child as a gay couple.' The reality is, he can do that. In a universe where at one point you couldn't do that and now you can do that, that's a much more positive statement that he's making."And for those hoping for a wild resurrection of Charlie Sheen's Charlie Harper, don't hold your breath. "We're not having those conversations right now," Tassler said.Other highlights from Tassler's executive session:Big Bang Theory

 contract negotiations: Although deals are still not in place for the five stars of TV's biggest comedy , Tassler said she is "very confident" the negotiations will be resolved before the show goes into production in two weeks. "We have successful shows and when you have successful shows, you have renegotiations," she said. "We're feeling very confident that everything will work out. These deals always get miraculously done."

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Late Night changes: Tassler said the network is in the middle of setting the timetable for the transition between David Letterman and Stephen Colbert, as well as having very cursory talks about the details of Colbert's new Late Show. "He does want the interview format," Tassler said, noting again that he will retire his Comedy Central character and may or may not have a band. However, bigger formatting changes may be afoot when it comes to filling the 12:30 timeslot and replacing Craig Ferguson on The Late Late Show. "We're looking at it through a different lens," Tassler said "The knee-jerk reaction is to go for another traditional, behind-the-desk interview show. There is an opportunity to look at all types of hosts — not just from the comic world, there's the political world." Tassler also said that, whatever new format the show takes, there is the possibility that they may rotate hosts for a while as the network did when replacing Craig Kilborn.
Is How I Met Your Dad dead
? Tassler seemed open to continuing discussions with How  I Met Your Mother creators Craig Thomas and Carter Bays about future projects. "We adore those guys and we want very much to stay in business with them," she said. Including a new take on the Dad pilot? "Some things worked, some things didn't and we'd love to take another shot. As I've said many, many times, Big Bang would not be Big Bang without having redone that pilot. I could not imagine Kaley Cuoco not being a part of that show."

Carter Bays: How I Met Your Dad isn't happening

More Under the Dome? Tassler seemed confident about the prospect of more Under the Dome . "I feel good. We haven't had those conversations yet. It's still very early. But I love the creative," Tassler said. "I love where we're heading toward the end of the season, so we'll see. We're doing great." But if this were the last season, could the producer wrap it up? "They're pretty  nimble. They're pretty smart," she said. "They could do it very quickly if they needed to. But right now, I'd love [for] the show to continue."

Long live NCIS: Tassler took a little time to gloat about having the biggest show, not just on network TV, but the world. "Our competitors may call [NCIS] old-skewing, we call it a billion-dollar franchise," she said. However, when pressed about her concerns that CBS has fallen to third place in terms of 18-49 demo ratings, Tassler said, "We're in a transitional phase. If we're only going to talk about 18-49, I may as well get out of my chair and turn my television [dial] manually. ...There are many more standards by which we are measured. Definition of success is changing, it's evolving. I think 18-49 is just part of the conversation."

On Emmy snubs: Tassler didn't mince words. "I'm still really pissed about The Good Wife," she said. "I'll hold up The Good Wife to any show on TV, cable or broadcast. That's a great quality show." When later asked about the quality of that show relative to other network shows, including those on her own network, Tassler said, "We always strive for excellence across the board. Our goal is to produce the best content, our goal is always to hire best actors and be in business with the best writers. As broadcasters, we ask ourselves, are we entertaining the greatest number of people and are we making the most amount of money doing that? We have to hit that creative holy grail.

Full disclosure: is owned by CBS.