There is something very Eddy and Patsy about Absolutely Fabulous getting an in-depth, bells-and-whistles retrospective, not for its 25th or even 30th anniversaries, but for its … 32nd. Absolutely Fabulous: Inside Out is an indulgent treat for fans, bulging out of its Lacroix sample sizes with gossip, memories, outtakes and a warm, if too brief, cast reunion. If, like many of the talking heads here, you believe it to be one of the greatest British sitcoms of all time – and it is, obviously, particularly the first three series – then this is a fantastic and revelatory deep dive into who and what made it so special.

As regular listeners of the French and Saunders podcast Titting About will know, Dawn French took some time away from their double act in the early 1990s to raise her daughter, leaving Jennifer Saunders without her comedy partner and in need of a new project. Saunders admits that at that point, her writing experience had been limited to sketches. But one of those sketches, Modern Mother and Daughter, saw French playing a Saffy character, and Saunders the mother, then called Adriana. You can see how much of the show is there already. It only needed the addition of best friend and fashion editor Patsy – whom Joanna Lumley poetically refers to as a “succubus … like ivy, or one of those insects that feed off you” – to flesh it out. If a single sketch could be nine minutes long, Saunders reasons, you only needed to put two of them together to call it a sitcom.

There’s a lovely against-the-odds narrative throughout. Saunders’ approach to writing Ab Fab appears to have been, shall we say, scattergun, and that was on a good day. The first series was largely written in advance, but later episodes would be worked out in the rehearsal room, with a lot of cigarettes (“We liked all the smoking,” says Lumley). Ruby Wax, who script edited, remembers one script that, in lieu of a written scene, simply said “something funny happens”. To Saunders’ credit, it did. It was so slapdash that Lumley admits she asked her agent to try to get her out of playing Patsy, who said that she should film the pilot anyway, and that it probably wouldn’t take off. Producer Jon Plowman remembers former head of comedy at the BBC, Robin Nash, sitting through the dress rehearsal for the pilot and noting afterwards that he never had found women being drunk very funny.

But plenty of viewers did, and it was a smash hit: the sort of crowd-pleasing comedy, as the director Emerald Fennell says, that only comes along once every decade. To watch it now, for the hundredth time, is to be reminded of how fantastically anarchic it is. The jokes still have fangs, and, to its credit, this doesn’t retrospectively clutch its pearls at some of the more outrageous ones: Patsy telling Saffy that she should have been aborted remains one of its most quotable and most vicious moments. Lumley says she asked if she really had to say the line, and Saunders, of course, insisted she did. This is a timely reminder, too, that as Patsy, Lumley puts in one of the greatest physical comedy turns in TV history, and she still doesn’t get nearly enough credit for how perfect a performance it is. Patsy simply eating is so funny that the cast can’t even talk about it now without cracking up.

Kirsty Young narrates, Saunders unearths her original notes, and it parades costumes from the archives, all of which give the documentary a national treasure-style gravitas. But what really makes it sing are the anecdotes, as unfiltered as Patsy’s liver. Wax talks about the inspiration for Edina, long rumoured to be the one-time PR guru Lynne Franks. The story she tells about sharing a taxi with Franks, and how that led to at least one part of Eddy’s character, is exquisite. Saunders, meanwhile, reveals another, more niche inspiration: Adriana Ivancich, the Italian noblewoman and teenage inspiration for Hemingway’s 1950 novel Across the River and Into the Trees.

June Whitfield, who played Mother, died in 2018; the last time the cast all got together was at her memorial. Jane Horrocks joins Julia Sawalha, Saunders and Lumley for a glass of Bolli, as they look over old Polaroids, watch outtakes and discuss which scenes they couldn’t get through because they were all laughing too much. It might sound luvvie, but it avoids that by sheer force of being so frank and entertaining. And above all, you get to see Saunders and Lumley watching old footage and laughing their heads off. “It was amazing, what we got to do, and it’s just a little comedy, and I loved it,” says Saunders. Delicious.

Absolutely Fabulous: Inside Out aired on Gold.