You'll never guess who's running the Buy More in Chuck season four!S

NBC's Chuck will be following in the footsteps of Alias, swapping daddy issues for mom mysteries. The search for Chuck's mom will drive the fourth season, producers told Comic Con. Spoilers ahead...

The Chuck panel at Comic Con was hilarious - first there was the announcement of Linda Hamilton was playing Chuck's mom, and then the video screens filled with an Intersect test, that would kill most of the audience members. "Have a nice day," the message said, before bombarding us with a bewildering array of images. And then Chuck and Morgan appeared on the screen. Chuck introduced himself as Charles Carmichael and then Morgan said he was Javier Bardem - to which Chuck retorted that this isn't how cover names work, you can't claim to be a real living person.

They searched for a video to put on, to forestall the Ring from showing us the lethal Intersect test again, and rifled through DVDs marked Tron Legacy, The Avengers, Captain America and Serenity, before putting on something called Jeffster Dance Video - which turned out to be Jeffster doing some killer moves to Lady Gaga's "Bad Romance." Mostly Lester dancing while Jeff spritzed him, in front of a greenscreen which turned into various insane backgrounds.

And then Jeffster came out on stage, dancing in the same outfits they were wearing in the video.

A lot of the panel and discussion in the roundtable interviews afterwards had to do with Chuck's mom. We'll glimpse Linda Hamilton in the first episode, and we'll see more of her after that. During the roundtable interviews, we asked producers Josh Schwartz and Chris Fedak whether they were thinking about Alias when they decided to shift the focus to Chuck's mom, and Fedak said:

Absolutely. The Chuck writing staff is a very nerdy staff, and we really enjoy spy shows... The moment you start talking about a spy mom you have to consider other shows [and] Alias is something we've considered, as well as things that have happened in other shows that have introduced this type of character. And also with the casting of linda hamilton, we wanted to find someone who could kind of be two things: a perfect mom-type character, but also someone who would have have this flipside that would be fun for us. In our first episode we really subvert the expectations [of the audience].

And where the "flipside thing comes in is that Chuck's mom is kind of a scary spy, who can be a sweet mom and then suddenly show her intense spy side.

So the Buy More was blown up at the end of the last season, but it'll be back this year — only now, it's wholly owned and operated by the CIA, staffed by elite CIA operatives. Big Mike will be sort of a front man, who runs the place but doesn't really know what's going on. "Big Mike, I don't think should ever find out the spy world, because in spy films, the black guy is always the first to go," joked Mark Christopher Lawrence in the roundtable interviews.

In the first episode, Olivia Munn will appear as Greta, a Buy More exec who's also a top spy. And in every episode after that, there'll be a different Greta, who'll always have that name regardless of gender. The second episode's visiting Buy More exec? Isaiah Washington, the "I'm on a horse" guy from the Old Spice commercials. Other guest stars include "Stone Cold" Steve Austin and Dolph Lundgren.

Chuck and Sarah will be a full-blown couple this year, and the producers said they've learned their lesson about putting anyone in between those two. Also, in the roundtables, Ryan McPartlin hinted that Ellie and Awesome will be refocusing on their home life now that they think the spy craziness is over — and this may mean a little Baby Awesome could be on the way. We'll find out more in the first episode, McPartlin said.

The last person to know Chuck's a spy will be Jeff - and chances are he wouldn't even remember it the next day, said the producers.

The big conflict of the season will be Chuck being torn between his father asking him to find his mom, and Ellie asking him to quit being a spy. He'll be torn between those two promises, and he'll try to juggle them. Ellie will once again be in the dark about Chuck's activities, because she'll believe that Chuck is keeping his promise to quit spying. So in fact, even though Ellie's learned Chuck's secret, not much will have changed in their relationship.

Oh and someone asked Adam Baldwin during the roundtables what his secret for playing the perpetually snarling/sneering Casey is, and he said it's an acting technique called "substitution." He has a mantra running through his head all the time, saying "I hate people." Or sometimes, "I hate incompetence." Which makes it even funnier that Casey is frequently incompetent himself, and gets himself "beat up by girls" on a regular basis.

Chuck returns to your screens on Sept. 20.