Mr Foote's Other Leg (Hampstead Theatre)

Here's a right old how-de-do. Ian Kelly's enjoyable kerfuffle of a play features Simon Russell Beale as a foul-mouthed one-legged comedian called Foote, a jar full of penises, a quick guide to the Georgian theatre of Charles Macklin, David Garrick and Peg Woffington, a rag bag of old gags ("The opposite of comedy is Germany"), a grisly onstage amputation and a visit from King George III.

Kelly has "freely adapted" his own biography of Samuel Foote, a West Country impressionist and actor manager who was granted only the third royal patent – for a theatre in the Haymarket, next to the original Haymarket – after the Licensing Act of 1737 (which created the censorship we only got rid of in 1968) on account of his outlandish cheek and his misfortune; he lost the leg after a riding accident.

Richard Eyre's frenetic production, riotously designed by Tim Hatley, is an echo chamber of several other plays, notably Alan Bennett's The Madness of George III – Russell Beale's Foote is a Lear shadow, complete with Handel, piss-pot and thunderstorm, just as Nigel Hawthorne's monarch was in the Bennett; both actors had less success as Lear proper – with actors ejaculating Hawthorne's "what-whats" soon after three others have tumbled over the stage as identical fuzzy-wigged blackface Othellos, re-enacting a farcical mayhem scene in Ken Ludwig's Lend Me a Tenor.

The playwright himself plays George, first as a prince, then as a king, with a fine theatrical disdain, though the piss-pot in this case is Foote's, as he tries to save an actor Garrick has pierced through the eye with a puddle of his own piddle. It's good to see Russell Beale snarling with vulgarity like a raddled old pole cat as he belittles Joseph Millson's handsome Garrick for his devotion to the Bard and Festival project in "Stretford," or trades affectionate insults and crude gossip with Garrick's doomed lover, Peg Woffington, deliciously played by Dervla Kirwan.

Foote was finally done down, like Oscar Wilde, on a sodomy charge, though we only see here his unrequited affection for his Jamaican dresser, Frank Barber (excellent newcomer Mican Balfour), a character more associated in history with Samuel Johnson, and also, incidentally, Britain's first black schoolmaster.

Other historical avoirdupois is entered by the surgeon John Hunter (Forbes Masson) who saws off the leg on the Haymarket stage with much tugging and tearing ("Bloody hard to top that in the second act," snaps Foote) and physicist Benjamin Franklin (Colin Stinton) whose theories of electricity run parallel with Hunter's phrenological discussion of acting and consciousness.

Yes, well, there's an awful lot crammed in there, as the actress said to the bishops, but it's all lightly discharged, and not even overshadowed by news of America's Declaration of Independence in 1776, the year Foote's troubles coagulate. He gathers himself for one last turn as his dignified Dame Edna alter ego, prefaced by Handel's "Lascia ch'io piango" – one of the most gorgeous arias ever written, and currently featured, too, in another courtly theatrical extravaganza, Farinelli and the King, starring Mark Rylance – an ironic come-uppance for Foote, who loathed Handel, or at least affected to. Kelly's play offers Russell Beale a witty and surprising way of reprising his Lear just as Charlotte Jones's Humble Boy furnished him with a disarming warm-up for Hamlet.

Mr Foote's Other Leg continues at Hampstead Theatre until 17 October