Here is a 70s time capsule as pungent as a brimming pub ashtray. Restored and rereleased, Big Banana Feet is the 1976 documentary about Billy Connolly’s live shows in Dublin and Belfast the year before, just after his appearance on the BBC’s Parkinson show made him a star virtually overnight, and allowed his legions of new fans to hear him live and unexpurgated. Billy and his hangdog entourage – all looking like a very downbeat version of the Bay City Rollers – travel to Dublin then to Belfast by private plane, but aside from that, everything looks very non-luxury. The backstage areas have the air of a scout hut, and there don’t seem to be any riders with Jack Daniel’s, cocaine, only-green-coloured M&Ms, and the like – Connolly gets a pot of tea backstage so stewed it has to be poured like treacle. The press gets an enormous amount of almost unmediated access to him, including a meet and greet before the show – despite his plaintive requests that this shouldn’t happen – and afterwards too. And the morning after his first big night at Dublin, he is prevailed upon to get up early for a radio show; he does it all with absolute politeness. The nearest Connolly gets to being annoyed in the entire film is when he realises his support act is playing a banjo, thus rather upstaging the bluegrass part of his own set. Frankly, a lot of Connolly’s naughty material hasn’t aged very well and he got away with quite a lot of dross, perhaps because adult comedy was not a saturated mainstream market in those days. People were more used to the daring satire of Dave Allen, and in comparison Connolly was an innovator. Connolly certainly was proto-alternative and proto-punk, and these were febrile times. At the Dublin show, a heckler shouts “IRA!” and Connolly replies acidly: “I’d love to hear you say that at Ibrox [Rangers’ stadium in Glasgow] …!” It’s amazing, from this modern perspective, to experience again how sectarianism was a violent and normalised fact of life in the 70s. In Belfast, Connolly prudently drops any material about the Troubles, perhaps because he simply and understandably doesn’t want to take the risk. When he arrives at Belfast airport, Connolly chats amiably to soldiers from 15th Battalion of the Parachute Regiment, which he was once with as a Terrritorial Army reserve, and we hear his melancholy song about this on stage, Weekend Soldier‚ easily the best part of his show. It is what Connolly says offstage that is now amusing, rather than his actual act. When he and his crew are at the airport, a voice over the tannoy requests a “Mr Jamaica”; Connolly ponders that it feels like a Mr Universe candidate is being paged. “And then a white skinny guy gets up!” He also explains how someone made his famous banana boots and this man said to him: “They’re not identical … but then bananas never are.” For a second, Connolly’s material sounds like Alan Bennett’s. Billy Connolly: Big Banana Feet is in UK and Irish cinemas from 10 May.