The comedy in Tom McGrath's tribute/biography play Laurel and Hardy relies on the two performers' powers of mimicry to succeed. The theory goes something like this: if Neil Bromley and Simon Lloyd (the leads in this Jermyn Street Theatre production) can accurately mimic Stan Laurel and Oliver Hardy, then the play will be funny, because Laurel and Hardy were funny.
I needed the programme just to remind me Hardy was the tubby one, so I'm supremely unqualified to judge Bromley and Lloyd's impersonations - though thankfully the play provides a handy beginners' guide to the double act about twenty minutes in, so even Laurel and Hardy virgins aren't totally alienated.
Still, it's simple to guess which are the better-known mannerisms by the reaction of die-hard fans in the audience. Lloyd preens, fiddling with first his tie, then the brim of his bowler hat; Bromley waddles flat-footed and absent-mindedly scratches his head; the crowd goes wild.
These actions aren't funny in themselves, or I'd be laughing too. It's familiarity, and delight at seeing live actors perform gestures normally viewed in fuzzy black and white, that influences such a positive reaction. And that reaction is the real indicator of the play's success: its target audience, Laurel and Hardy fans, give it their vocal seal of approval.
McGrath, who died in April, did his duty as a playwright as well as a fan. While Act One consists mostly of reconstructions of the duo's routines, Act Two focuses more on their offscreen lives: spats over contracts, failed marriages, health problems and the evolving movie industry that eventually rendered their act irrelevant.
Whether it feels ironic or not for McGrath to point out the irrelevance of the act he's reanimating depends on your stance on Laurel and Hardy. Their brand of slapstick tends to be thought of as low humour these days - but they clearly still have devoted followers.
The play is set in a stained-glass antechamber, a "waiting room between this world and the next". Laurel and Hardy are dead, and their humour is outdated; but not everyone's ready for them to move on just yet.