The only thing that grants farce artistic credibility is the precision of its construction. Otherwise, it's no better than circus clowns falling out of exploding cars. Sir Richard Eyre is the latest director to take on Sir John Mortimer's sublime translation of Georges Feydeau's A Flea in Her Ear and those knighthoods show that respected directors need feel no shame in becoming farceurs, in one case, and that farceurs are rewarded by the establishment, in the other.

If Feydeau had not spent his life writing his 39 plays, he might have been a terribly good watchmaker or, given his sense of humour, perhaps a manufacturer of handmade cuckoo clocks. The script of the first act of Flea begins with a description of a respectable, bourgeois drawing room in Paris. The designer is ordered to provide French windows, double doors leading to a hallway, corridors "to R and L" and three more doors to inner rooms. In the play, there are 247 occasions when these doors and those of the Hotel Coq d'Or, the location of Act II, are opened or closed. If that doesn't persuade you of Feydeau's genius, nothing will - not even a production that runs like clockwork as perfectly as Sir Richard's.

Instead, you will note the revolving bed in the Coq's main bedroom. You will frown and conclude that the only reason it is there is to serve as a prop. It is, certainly, the play's weakest device, only partly redeemed by the line, as the bed turns and disappears: "We'll file you away for future reference."

Usually in farce, it takes time for the clock to be wound and the process here is slightly frustrating. Camille, the nephew of Victor Émmanuel Chandebise, in whose drawing room we are, is particularly irritating - he speaks in a mangled screech caused by a cleft palate. He is all but incomprehensible, the more so thanks to the brio of Freddie Fox's performance. In a sense, he is a mirror image of the whole play: when a doctor provides him with a prosthetic palate, he turns from farcical lech into credible lover, just as the rest of the cast has its credibility stripped away. Also dragging Act I down is Victor's wife, Raymonde, as rendered by Lisa Dillon, a disappointing character with plenty of plot explication to do. She tells her equally dull friend Lucienne (Fiona Glascott) that, although she has a lover herself, she is afflicted by the suspicion that Victor is unfaithful. The pair plot to trap him by sending him off to an assignation with a non-existent admirer at the aptly named Coq. The loudest sound in the auditorium is the winding mechanism.

The act is soon saved, however, by the arrival of Tom Hollander as Victor. Hollander will, I hope, forgive me for saying that his big, expressive head and his little, busy legs (always trying to keep up) make him a natural comic actor.

His stature - Hollander's gift to the part - at once renders smug Victor likeable. When we hear that he is suffering from impotence, we sympathise as much as laugh, although we do that, too. (Victor: "I felt I'd become a little child again." Doctor: "That was a bit hard." Victor: "You could put it more happily.")

At the Coq, his doppelgänger awaits - the drunken porter Poche, who soon finds himself socially elevated in the confusion. And Victor is rendered the lowest of the low, receiving frequent boots in the bottom from the hotel's sadistic, ex-military proprietor. Hollander is a triumph in both roles, a diptych of the class system and a study in how circumstances can simulate symptoms of madness.

Is it all meaningless, as Libby Purves claimed in a dissenting review in the Times? I am not so sure. Farce points to one truth about the human condition: calamity and indignity will befall the innocent as much as the corrupt. Victor, whose only small sin is complacency, is disproportionately undone but, much as we like to believe character is destiny, it isn't always. By Act II, I was laughing to Feydeau's merciless mechanistic order, and so were most of us.