As the Monty Python team prepare to hit the stage this evening, Michael Palin reveals to HuffPostUK that he hopes he has the stamina to cope with entertaining the huge O2 crowds for the next three weeks.
"I have the mental energy," he says. "I hope I have the physical energy to do all these things.
"Python is going to be interesting. I'm confident that we will enjoy playing the sketches because we do like playing comedy, it's the one thing we all like doing together unequivocally happily.
Here are the Pythons rehearsing for the show in June - making each other laugh as always...
"Every other aspect of Python life is contentious or complicated, but being on stage, doing the comedy, we love doing that. And they're the best people to play comedy with, so I'm really looking forward to that."
Michael pauses to take a sip of tea, and I sense a "But..." Sure enough...
"It is in this huge place (London's O2 arena) with great expectations, and I know really that, however much we rehearse and plan, we will not know until we step out on that first night, exactly how it's going to work… how much noise there will be, how much they'll listen to us and all that sort of thing, so it's exciting in a slightly apprehensive sort of way."
Like young rockstars lining up for more love and applause?
"Yes, but we're not, we're 70-year-olds," he reflects. "I see Fleetwood Mac and everyone, they're 102 and playing their guitars and that's fine, and of course Mick Jagger is the patron saint of longevity. But we've got to act, and we've got to change our trousers 15 times in an evening.
A BBC documentary shown at the weekend revealed that fans will be treated to many familiar sketches from the Pythons' archive, filled in with lots of song and music. The show has been organised for the main part by Eric Idle, who has lots of showtime experience with his great hit 'Spamelot'.
Is the expectation from the fans, the critics, the longtime purveyors of Python who can quote every line even though it made its debut nearly half a century ago, overwhelming?
"I think strangely enough it carries me," says Michael. "If we'd announced the O2, and just been able to fill a couple of nights, I would have felt, 'Oh gosh, how's it going to go?' but the fact that we filled five nights almost within two or three days, now that's frighteningly unexpected, but it's good because we know those people do want to see us.
"So provided we don't fall off the stage or go into a coma half-way through, they'll think they've got their money's worth. But that enthusiasm, we have to pay it back in the way we perform, the way we put it together.
"We're all pros, and it will be a test of our professionalism combatting the corrosive effects of old age."
Michael Palin professes himself amazed by the level of enthusiasm for the group - Michael together with Graham Chapman, John Cleese, Terry Gilliam, Eric Idle and Terry Jones - that originally joined together for jinks in 1969, and heralded a comedic revolution that continues to inspire today's comics.
"We knew that this was going to be something that might keep us in the public eye for a couple of years, and that would be that.
"By the second or third series, there was that slight feeling in the back of the mind that maybe this could go on for a year or more, but the idea of it still being around, and loved, and quoted 45 years later…
"I don't know why 'Nobody expects the Spanish Inquisition' should be funny. I don't know why Margaret Thatcher got such a laugh in parliament when se likened the Liberal Party to a dead parrot..." He shrugs and smiles... "But there we are. Something clicked."
Nearly half a century later, I wonder if, through all his travels, his readings, his writings, his always impressive turns in drama including, most recently, as General Mitford in the award-winning 'The Wipers Times', Michael Palin's sense of humour has changed at all?
"No, I still laugh at silly things," he admits. "I used to enjoy slapstick when I was young - people like Norman Widsom and Laurel Hardy - and now, someone slipping on a banana still gets me.
"It's those little moments when you see the human race doing something patently absurd and I'm attuned to that still."
Monty Python play their first show at London's O2 arena on 1 July. Details here...
Michael Palin begins his 'Travelling To Work' tour in September. Details here...