​Coldplay in the adventure of a lifetime

The rock group Coldplay is warming up for a very high-profile performance next Sunday night, and they're leaving nothing to chance, as Anthony Mason will show us:

On the lot of Sony Pictures Studios in Los Angeles, in Soundstage 14, Coldplay started rehearsals this past week for their Super Bowl halftime show.

"This is the Super Bowl stage, without any of the gadgetry," explained Chris Martin.

"So you've basically created a stage that's the same size as the Super Bowl stage?" asked Mason.

"Hopefully!" he laughed.

For Coldplay's four principals -- guitarist Jon Buckland, drummer Will Champion, bass player Guy Berryman, and frontman Chris Martin -- it's the biggest gig of their career.

"What's the audience for this? It's like a gazillion people," said Mason.

"I think it's three gazillion, actually," Martin clarified.

"If something goes wrong, that's gong to be a big part of it," said Buckland.

Martin added, "My daughter said the sweetest thing yesterday. 'How you feeling about the Super Bowl?' 'Of course, we're a little bit nervous.' She said, 'Dad, the worst that could happen is you'll get turned into a meme. And after a month or so people will just forget!'"

Coldplay's Chris Martin with correspondent Anthony Mason. CBS News

Their biggest show will also be their shortest: "I loved the whole concept of trying to present your entire musical life in 12-and-a-half minutes," Martin laughed. "It's a great challenge!"

"Have you figured out what you're going to do yet?"

"We've possibly got 11 good minutes. So we have some special guests and they'll cover the rest."

Those guests have not been officially named, but there have been plenty of hints on the stage: "This may be Beyonce's footprint," laughed Martin. "I'd say she was here about four hours ago. Let's look for a Bruno one."

Beyonce, who's in Coldplay's new video for the song "Hymn For the Weekend" (below), is expected to join them with another halftime show veteran, Bruno Mars.

"I spoke to one of the other artists who did it a few years ago, and he said, 'It's gotta be muscle memory," Martin said. "Well, I'll tell you, it was Bruce Springsteen, 'cause I realized I was starting to do his gruff accent: 'You gotta know every note, man. Twelve minutes. It ain't long, but it's long enough!'"

The British band that broke through behind their hit "Yellow" in 2000, and has sold some 80 million records, will celebrate its 20th anniversary this year.

Mason asked, "Does it feel like 20 years?"

"No. Not at all. More than half our lives," said Buckland.

"Will and Guy said you guys are as close as probably you've ever been."

"Did they? That's good!" laughed Martin. "Whatever they say, we do."

"I find that we're in this sort of weird limbo," said Champion. "We're not an emerging band anymore. We're no longer a new band. And we're certainly not quite that sort of heritage value."

Berryman explained: "We're entering a new phase of denial about how old we are."

"It's the midlife crisis!" said Champion.

They are, as one critic called them, "the biggest, youngish rock band going."

"We only just had the 'ish' added. Now we're 'ish," said Martin.

But do they feel "youngish"? "I'm happy to be called youngish, I think. Feels good," said Buckland.

Martin asked, "Is 'ish' a compliment?"

It's far from the worst thing Coldplay's been called. The New York Times once branded the mellow rockers "the most insufferable band of the decade."