'How I Met Your Mother' At Comic-Con: Cast Talks 'The Mother' Reveal And What To Expect From The Final Season (VIDEO)

"How I Met Your Mother's" first and final Comic-Con panel kicked off with a special video featuring the kids (now noticeably older) letting loose an expletive-laden rant at Ted for taking eight years to tell the story of how he met their mother. "We've gone through puberty on this couch ... We've been s----ing in a bucket!" the son points out in the video above.

Then the cast emerged to ear-piercing screams and a standing ovation. On the panel were Jason Segel, Cobie Smulders, Neil Patrick Harris, Alyson Hannigan, Josh Radnor and executive producers Carter Bays, Craig Thomas and Pamela Fryman.

After the initial excitement died down, Radnor -- who plays Ted -- opened up about the elusive mother, played by Cristin Milioti, who finally made an appearance at the end of last season.

"It was weird, there was some relief on the show when we finally revealed [the mother], mostly so people would stop stopping me on the street and shaking me and saying 'who's the mom?!" Radnor shared.

Ted's been frustrated about his love life for a while, but Radnor pointed out, "you know this guy wins in the end, it's not a nihilistic show ... things happen and then there are consequences, everything happens for a reason in the world of 'How I Met Your Mother.' Ted's been bruised but that's okay, because he gets the life that he's been dreaming about ... we see him with the couch and the foul-mouthed kids, just not on his timetable."

And according to Neil Patrick Harris (Barney Stinson), longtime fans of the show won't be let down.

"[Radnor and Milioti] filmed a scene together last week and they are an amazing couple on screen," he said.

As for how the show will end, series creator Carter Bays was willing to drop a few hints.

"We don't want to give anything away, we don't want to tell you what you'll find out or when you'll find it out," he teased. "Creatively, [what made us want to do a final season is that] at one point the last scene was going to be 'here's this girl,' but like you guys, we want to know who this person is, we want to see Ted happy, we want to see the great moments that are ahead of him once he meets this girl. We're going to get to know this lady."

He also shared his hopes for what fans might take away from the final season: "This show has always been an affirmation of hopefulness and optimism ... It's a valentine to things like friendship and love, and I'd like to think that this season will sum that all up in one package."

As for how Season 9 opens, Bays promised, "It starts with everyone headed off to this wedding. We have this new framework ... the structure of it is that we're telling the story of the wedding, but we'll flash back and flash forward as we always do. Decades will be spanned in the course of this season!"

Segel will be working with previously announced guest star Sherri Shepherd in the final season, but remained tight-lipped on the details of her involvement, except to teasingly say, "there is some spark there."

Harris also shared a few more details on the return of Wayne Brady as Barney's brother, James. "It's Barney and Robin's wedding so you're going to see a lot of people you've seen before ... James is getting a divorce. That puts things into a little bit of a pickle," he teased. "It'll be great, I'm excited to have a lot of people back. I'm excited that she show is ending when it is, I didn't want us to beat a dead horse and be in Season 24 of 'How I Met Your Mother' and for you all to want us to go away."

The producers wouldn't confirm any other returning guest stars, but Bays said, "If there's someone you've loved over the past eight years, it's very likely they'll be back."

Smulders expressed hope that we'd meet Robin's mother, and that Lucy Hale would return as her younger sister.

Naturally, Marshall still has some slaps left to bestow upon Barney before the end of the series, and Thomas revealed an interesting tidbit about one of them on the panel. "There's going to be an episode that takes place over the course of one slap," he said. "We're going to get the tennis camera they get to capture Roger Federer's serve and use that slap as a framing device for the entire episode. And there may be a musical number."

The working title of the next slap episode is "Slapsgiving 3: Slappointment in Slapmarra." Naturally, Harris wasn't so eager for this particular storyline. "I don't like the slaps, I don't think they're fun at all. Have you seen the size of Jason Segel's hands? They're mitts, they're huge -- they're like his penis!"

Smulders expressed her hope for another Robin Sparkles song before the end of the show. "It's such a fun thing to get to do ... It takes us out of the structure of our show."

Smulders may get her wish, given Thomas' response to whether we'd receive more Robin Sparkles before the finale: "It's a wedding, people sing songs at weddings."

Smulders then led the crowd in a rendition of "Let's Go to the Mall." Later, Segel reprised the song he wrote for the vampire musical in "Forgetting Sarah Marshall," followed by the "Bang Bang" song. The producers also have a variation of "You Just Got Slapped" coming up this season, sung by someone special they can't reveal.

Are you looking forward to Season 9?

"How I Met Your Mother" returns for a final season on Mon., Sept. 23 at 8 p.m. on CBS.

How I Met Your Mother