Let’s start with a word of praise for my favourite supporting player this season at Stratford-upon-Avon, scandalously denied a biography in the programme. It’s a stuffed crocodile, first seen hanging from the ceiling in Love For Love several months ago and now back for The Alchemist. Perhaps director Polly Findlay has read the late, great Terry Pratchett, who observed that such a prop “is absolutely standard equipment in any properly-run magical establishment.”

It certainly adds to the air of hocus-pocus and flummery here as Face, a butler left in charge of a London townhouse while his master flees to the country for fear of the plague, and Subtle, a fraudulent alchemist with whom Face teams up, set about bilking all-comers of whatever they have, from a twist or two of tobacco to a fortune in gold. (They also use the croc as a novelty piggy-bank for their swag.)

The third conspirator, the whore Dol Common, poses as everyone from the queen of the fairies to a half-mad nymphomaniac noblewoman. Subtle at one point describes her workings on a victim thus: “She must milk his epidydimis.” Wonderful phrase – it’s virtually incomprehensible (the epidydimis is part of the male genital plumbing), but there’s no doubt that it’s positively filthy.

Shakespeare’s near contemporary Ben Jonson loved language of all kinds, from high-flown classical verbiage to good old downright vulgarity: the second line of this play is “I fart at thee!” And in this, one of his greatest plays, he’s supplied himself with a rich variety of characters to give voice to all kinds of words. There’s honest Abel Drugger, who just wants a kind of Jacobean feng shui reading for his new shop; nobleman Sir Epicure Mammon and God-botherer Tribulation Wholesome, who are both after the Philosopher’s Stone; and Kastril, a young nobleman who wants to learn how to argufy like the city’s angry young blades... quite apart from the tricksters themselves, who come out with all kinds (and I mean all kinds) of nonsensical jargon.

It’s basically an excuse for a series of comic turns, that grow increasingly entangled in the manner of the best farces, until everything unravels with even more vim and vigour. Findlay and her cast, though, don’t engage in frenzied farcical rushing about; these are practised con-men, after all, unflappable even when pretending to row with each other. Ken Nwosu as Face and Mark Lockyer as Subtle are masterly, though Tom McCall steals his scenes as Kastril by managing somehow to be languid and turbulent at the same time. Jonson gets a raw deal these days, with allegations that he’s dense and incomprehensible. But pay no attention to those kind of alligators.

Written for The Lady.