“I was nibbled … but, because I was such a weedy, namby-pamby … I reacted as though I’d lost a limb. It was the sheer unfairness of it all that so upset me. One minute, I was saying, ‘Hello, Mr Bunny!’ and smiling at its sweet little face and funny floppy ears. The next, the fucker savaged me. It seemed so gratuitous.”

Cleese’s schooldays began with similar social difficulties. A love of comics led him to the notion that “kicking people’s bottoms was very funny, though in practice this didn’t make them laugh as much as it should have”. He survived to grow into an “uncoordinated and awkward … six foot of chewed string”, and ultimately recalls his school days as wonderfully happy.

Though drawn to comedy “with an intensity that almost defies analysis”, he had no thoughts of a comic career. After school he spent two “halcyon” years as a teacher at his old primary, where he learned that teaching was essentially a form of guerilla warfare.

Cambridge followed where, at Downing College, Cleese read law. He was conscientious: “I trudged off every day to attend every required lecture, at least half of which were deeply uninspiring.” Surprisingly, he didn’t leap immediately for Footlights, Cambridge’s famous comedy dramatic society. After an initial conversation, it was established he could neither sing nor dance: “I ran for it … And that was the end of my showbiz career. As far as I knew. Or cared! … After all, I was going to be a lawyer.”

Fortunately for us, Cleese was later drawn to the Footlights club room as a convenient place to eat crisps and spend time with “the nicest bunch of fellows I had come across”, one of whom was future Python Graham Chapman.

Cleese’s book is notable for his emotional honesty. Often memoirs of success breeze over early struggles, but Cleese, who is 75, embraces his fears and insecurities. At Cambridge he considered himself a dull fellow and not one of the strong performers in Footlights. When cast in the Broadway musical Half a Sixpence after university, the “degree of my flabbergastedness beggars description”. He couldn’t sing and as a dancer his “prancing (was) an imitation of a man in battle trying to avoid one of those chariots with nasty sharp knives sticking out of their wheels”.

Cleese had stage fright in his Footlights days, and this continued through his pre-Python work as a television actor. Before his first live TV performance, on The Frost Report, “I sat and watched the second hand on the wall clock as it steadily ticked off the final moments”, feeling “TOTAL DREAD”.

Although famous for physical comedy, Cleese considers himself more a writer: “I did not view the world as an actor does, and I never thought of myself as one.” In the late 1960s, he and Chapman chose to become full-time writers and loved it. Cleese felt “much more at ease now that I was free of the nerves I had experienced whenever I had to stand in front of an audience”.

The writing process was a joyful one: “Gra and I … would suddenly be possessed by this bolt of gleeful energy … the screaming and howling with laughter would go on for some time before we actually settled again to write it down.”

Since the memoir focuses on his early years, Cleese’s time with the Pythons gets limited space (hopefully volume two is in the works). But what we do get is gold. There have, Cleese writes, “only been about four occasions in my professional life when I have shown any real initiative”. One of these was suggesting to Chapman that they contact the other four Pythons-to-be: Terry Gilliam, Eric Idle, Michael Palin and Terry Jones. They had an inauspicious beginning, walking into a BBC pitch without having discussed what kind of show they were going to make and “looking clueless”.

Happily, they were commissioned. But it took them a while to come up with the name Monty Python’s Flying Circus. An initial contender was Owl-Stretching Time. There is, Cleese says, one essential fact to understanding how the Python group operated: “(we) were primarily writers, not performers”, “invested in our scripts, and not in our acting”.

That investment sometimes led them “into very silly territory”. Deciding that a set should be lit with a “dead stuffed farm animal with a light bulb in each foot”, there followed “the utter ridiculousness of five Oxbridge graduates fighting ferociously over a simple choice between a sheep chandelier and a goat chandelier”.

The next generation of British comedians worshipped Cleese. Fry, who at 57 is almost 20 years younger, writes in More Fool Me that working with this “towering hero from my early teens … made me rub my eyes with disbelief”.

This is Fry’s third memoir and, while it recaps his school and Cambridge days (subjects of Moab is My Washpot and The Fry Chronicles), it focuses on the early years of an impressive entertainment career. In the late 80s and early 90s, Fry enjoyed “preposterous success” in television, film, stage and print. He also enjoyed cocaine. A lot. “Cocaine,” he writes, “Oh dear. This has to be played delicately.” Indeed. Here goes.

More Fool Me functions, in part, as a drug memoir about Fry’s 15-year habit. “I have tried,” he says, “to make this book as balanced as possible, by which I mean true … I don’t want (it) to be a snivelling apology, nor a boastful ‘Coke, fuck-yeah!’ ’’ But “it would be wrong of me at least not to — as it were — give you a sniff of the coke years”.

Fry appreciates that some readers will be horrified, because they “thought better of me than this”. “I can’t begin to explain it,” he says, “but I can at least attempt to describe it.” And he does, in typically polite, eloquent, and rather bashful fashion.

“I didn’t take coke because I was depressed or under pressure,” Fry says. “I took it because I really, really liked it.” Sober, Fry hated parties. Cocaine gave him “a second existence. Instead of performing and being in bed with a mug of Horlicks and a PG Wodehouse at 11pm … I was a new, sociable, fun-loving Stephen”, able to stay out till near dawn then be ready to work at 10am. “It didn’t stop me writing or performing”; it was “the reward … the pudding”.

Fry recounts his cocaine use in detail, giving us the how (sniffed from “the side of your clenched fist … like a Regency snuff-taker”) and the where (a “list of shame” including Buckingham Palace and the House of Lords). Occasionally, it feels like a Breaking Bad script mixed with an episode of QI: “A part of me,” he says, “wants to show you what a wrap looks like, using an origami-style diagram with dotted lines.”

Ultimately, Fry concludes he was “irremediably foolish” and “shak(es his) head in wonder at the reckless, impulsive, stupid, vain, arrogant and narcissistic headlong rush into oblivion … Believe me when I say, if you are younger than me, that you will not make it if you think you can imitate my wicked, wicked ways.”

More Fool Me isn’t all coked-up debauchery. These were the years of Blackadder Goes Forth, Jeeves and Wooster and A Bit of Fry and Laurie on TV; of Kenneth Branagh’s film Peter’s Friends, and Fry’s first two novels, The Liar and The Hippopotamus. He wrote reviews and articles, later published in his Paperweight collection, and, rather less-glamorously, recorded voice-overs “for face creams and dog biscuits”.

Fry ends the book with his diary entries for 1993, the year he turned 36. Imagine Bertie Wooster with a fax machine, a motorbike and a cocaine habit and you’ll get close. “Zimmed round to Emma (Thompson)’s house,” reads one entry. “(W)riting with Hugh (Laurie) all day until biffing off to the Garrick for a drink”, reads another. This one could come straight from Wodehouse: “At two-thirty in the afternoon I slipped into a good shirt, knotted the silk salmon-pink and cucumber-green Garrick Club tie around my neck, selected some unassuming trousers and a pleasing jacket and trotted over to the Criterion Theatre.”

At times, the very different spheres of Fry’s life mix: “scored a couple of grams … and popped upstairs for a wine-tasting, which was charming”. There are also some truly eye-popping swears, worth looking at for the verbal dexterity if nothing else.

The diaries lead, apparently, “to a catastrophic explosion” (psychological, one assumes) but that doesn’t happen here: More Fool Me ends rather abruptly after the entries run out. And, I hazard to say, the diary goes on a bit. Golf and snooker are treated (as Fry says, about committee meetings) in “arse-paralysingly drear” detail. But then, I’m not a golfer or a snooker player. Perhaps those who are will bang their fists on the table and cry “Finally! My noble sport, immortalised!”

But Fry’s book is worth your time for the tour through his early years, living and writing with Laurie, polite hell-raising at the Groucho Club, dinners and drinks with the Pythons and Branagh, all delivered with Fry’s vintage plum, wit and sparkle. More Fool Me is, as a chapter heading says, “Very Naughty, But … In The Right Spirit”.