Comic-Con International creates the opportunity for all-star panels featuring talent from multiple mega-hit shows, and Thursday afternoon's “Brave New Warriors” panel saw a lineup that was at once unexpected and completely natural.

Matt Smith (Doctor Who), Kit Harington (Jon Snow from Game of Thrones), Steven Yeun (Glenn from The Walking Dead), Tyler Posey (Scott McCall from Teen Wolf) and David Giuntoli (Nick Burkhart from Grimm) played off each other in a lively chat with fans about the particulars of each series and each role, the broader issues facing actors, and some of the more unseemly parts of the business.

Entertainment Weekly's Lynette Rice, serving as moderator, began by asking how each panelist felt when first assuming his iconic role. Smith said it was "intimidating" taking over the part of the Doctor from David Tenant, who was regarded as one of the best actors in the long history of Doctor Who. "It was wonderful to be part of a show that had such a legacy behind it, but it was kind of strange,” Smith said. “There was such an uproar with my age, and everyone was like, 'He can't be the Doctor, he's 9!"

Harrington said he was pleased to have an HBO pilot, but could not have guessed at the success of Game of Thrones. "I read it, and it was just the most bizarre thing I'd read in my entire life,” he recalled “None of us had any idea of what it was or if it would work. I went into it not really knowing, and I love doing it."

Yeun said he'd only moved to Los Angeles about four months before landing the part of Glenn on AMC’s The Walking Dead. "It was my first pilot season, and I was happy to have a job," he said. "That job turned into something amazing."

When Posey's turn came, loud cheering erupted before he could answer, along with a shout of "We love you, Tyler!" After the Beatlemania-style screams died down, Posey said he was "super-excited" to get Teen Wolf, his first starring role. "First of all, it was Teen Wolf,” he said, to more cheering, “and I was super-stoked because it was MTV, and I love MTV. The role itself is just the coolest thing I've done in my entire life."

Giuntoli began by teasing, "I just want to speak for the fans, Tyler, and say that you are so sexy," which triggered even more screams from the crowd. He described his own series Grimm as "a very bizarre pilot," but "it came from some great guys like David Greenwalt, who was one of the boys behind Buffy and Angel.” (A mere mention of the two Joss Whedon series also elicited cheers, but on the level that Posey received.) Giuntoli added, “You feel very nervous, but very blessed to get the role."

Asked about the downsides of acting in genre series, Posey jumped in with, "The fan fiction is pretty nuts sometimes." A knowing laughter and more loud hoots arose from the audience. "But thank you, guys."

Yeun asked what kind of fan fiction Posey inspires, "because Glenn gets general Daryl-and-Glenn fan fiction. I love Norman, but ..."

He also spoke about having familiarity with the Walking Dead comics, recalling that his first thought was, "Don't mess it up, because I know how I would feel if someone came along and ruined my favorite character. I ... think I didn't do that?" he said, to cheers. As to whether his arc would follow that of his comic-book counterpart, he noted, "The show is kind of doing its own thing, so I'm just trying to do the best job I can."

Harrington also spoke about George R.R. Martin's A Song of Ice and Fire novels, which provide the story for Game of Thrones. "I read the books really quickly because I want to know what happens to me and how long I live for," he joked. "You just don't know at all with George." Although he noted that readers may hold Jon Snow dear to their hearts, "as an actor you have to separate yourself from people's expectations, and just take the character you've read and trust that your reading is the way people see him."

Smith described his four years on Doctor Who as "a privilege," but "when you've got to go, you've got to go." That elicited shouts of "No!" from the, by now, very worked-up audience. "It's sad, I'm going to miss it,” he continued. “I'm going to miss Comic-Con, as well.” Then, to cheers, he added, "Comic-Con's great, isn't it?"

Before moving on, Smith said, "Look, they'll get someone amazing, someone brilliant to do it. That's the great thing about the show, the strength of it survives, and it will get better and it will get bigger and it will keep going. And you'll forget all about me."

The moderator next asked the panelists to describe the "unsexiest" part of being an actor. Although Giuntoli was up first, Smith interjected, "The mornings are tough," and Giuntoli agreed.

Despite audience protestations that there is nothing unsexy about Posey, the actor countered with an anecdote. "I don't have any chest hair but I do grow nipple hair. I don't always shave it before a shirtless scene, so usually one of the executive producers shaves it for me," Posey joked. "I don't know why, he just wants to."

"There's lots of bugs in Atlanta," Yeun said of his unsexiest moments on set. "And they like the warmest parts of bodies."

Down the line, Harrington said, "My one sex scene was probably the most humiliating thing of my life. I broke my ankle at the time, so I had to crutch onto set naked. On crutches, not being able to hide ... anything. There's a hundred people, just ... trying not to laugh."

Smith, taking his turn at the end, joked "Karen Gillan in the morning is rough." More seriously, he said that learning the Doctor's lines is "like a kick in the nuts." Deciding that wasn't unsexy enough, Smith added, "Doctor Who's not a massively sexy show. You've got really quite sexy shows."

Rice then invited the panelists to do a take on EW's "Watch This, Sorry About That," having them apologize for work in their pasts. Posey took the lead, saying he's proud of his acting work but used to do Jackass stunts with his brother, "the grosser stuff" and "stuff having to do with my butt."

Giuntoli told the story of a job he didn't get: "I was this close, and I really wanted the commercial but I didn't get it. And thank God, because my first line was 'I have genital herpes.' And then [the girlfriend] would say, 'And I don't.' Then we'd both say, 'And we both want to keep it that way.'" Giuntoli's story shut down the game, as the other actors couldn't top it.

At that point the floor was opened to fan questions.

Asked what adventure he'd like to see the Doctor partake in, Smith said he'd always wanted to do "something with Sinatra; maybe Sinatra is an alien or something, I don't know."

One audience member asked how the actors felt about interacting with fans on social media. "I love having conversations with fans and think that's one of the only reasons Twitter be around," Posey said. Giuntoli said that "it's nice when you're on set to know that some people think I'm charming."

"I don't do Twitter," Smith said, although he did "venture" into it for a thank-you message to fans.

"I'm a real grump when it comes to technology." Harrington said, "I'm exactly the same as Matt; I'm useless. Anything with buttons." he added that he was afraid he'd write something that would "come back and bite me," and Smith grumbled "Yeah" along with him.

Asked about best friends on set, given the revolving companions on Doctor Who, Smith said, "I was really close to Karen and Arthur [Darvill], and the same thing with Jenna [Coleman]. It's because you're with them day in and day out."

The next fan wondered whether the panelists have any regrets for "taking a role you'll probably be known for for the rest of your careers."

"I hope that's not the case," Posey said. "I love playing Scott, he's one of my favorite roles ever, he's a super-iconic character and role. But I hope I won't be tied to this character for the rest of my life."

"I think that kind of nails it," Smith said. "No regrets."

"If you're lucky to do a TV series that does really well and you're recognized as that character, you're a lucky actor," Harrington said. "If you're known for a particular role, that's a great thing."

Asked about similarities between the actors and their characters, Harrington said that, "I can be a bit emo. If Jon had an iPod, it would have exactly the same kind of music on it."

One fan wanted to know about creepy experiences with fans. "It wasn't creepy,” Smith offered, “but once I came home and when I got to the front door, there was a little girl of about 12 in the bush. She was like, 'Don't worry! I'm not crazy!'" But after she went home, Smith thought, "That was really weird!"

Yeun's story involved a fan who "wasn't creepy, but I felt really bad for her." "We were filming in Atlanta and she saw me from maybe a block away, and she started zombie-walking towards me," he said, to laughter. "It was at least four blocks. And it was the greatest thing, because I could see her doing it and halfway through, I could see in her face, 'I regret this decision. But I will fight the good fight and continue on.' And the best part is, she gets up to me and says, 'Aaargh [in zombie voice]. I am so sorry.’"

One fan asked "If your character had to die, how would you like them to die?" Giuntoli replied, "It has to be big, it has to make me look cool." For Yeun, "It would be cool if I was riding a motorcycle, and then I jump off a ramp and I kill like 30 walkers, and then an explosion happens, and I land, and my heart can't take the strain of how awesome it was." Then, continuing, "I park the bike, I make sure I put the kickstand down, I dig my own grave, and then just fall asleep peacefully."

"For me, it's about to happen," Smith said. "It would be cool if I were in the TARDIS, and then I put my arms out and lots of golden light poured out of my hands, and then I turned into a woman!" Smith’s reference to the popular (if unlikely) suggestion that the next Doctor could be female drew hoots and laughter from the audience.

The panel ended with the actors revealing what disguise they would — or did — use to wander anonymously on the con floor. "I did it today as Bart Simpson," Smith said. "And I went to the Doctor Who booth and tried to talk to loads of people, and they were like, 'Who's the weird Bart Simpson?' No one talked to me!"