A contemporary look at Strindberg's bleakly farcical marital show-down in an artillery fortress should one day incorporate both parts of the play - not seen together since the great Laurence Olivier version in 1966 and a four-hour Riverside Studios production 20 years later with Alan Bates and Frances de la Tour - but Titas Halder's sparky production for the Donmar at the Trafalgar Studios season concentrates on only the first, scripted by Conor McPherson from a literal translation by Ian Giles.

Kevin R McNally - bloated, boiling with rage, extravagantly uncouth - is tremendous as Edgar, the drunken Captain on the wane, stricken by heart attacks, hideous to his wife, Alice (Indira Varma), and disastrously vengeful when her cousin and one-time lover, Kurt (Daniel Lapaine), arrives in the town to take up the post of a quarantine master.

Apart from anything else, he resuscitates one of the truly great monstrous modern roles, one associated with Wilfrid Lawson, Olivier, John Neville (at the Almeida) and, most recently, Ian McKellen.

Alice, a former actress, is 15 years junior to the Captain and tragically imprisoned in a marriage of stuttering inconvenience. And yet there is no escape, either from the impending silver anniversary, or the fortress tower itself. The piano is encrusted with candle wax, the door blows open to reveal not Strindberg's scrounging Old Woman but, who knows, an apparition of death?

The couple's permanent acrimonious banter is a rationalisation of their hellish condition. They squabble over the maid downstairs and her cooking (she leaves for good half way through the first act), they play a desultory hand of cards. And when Alice picks out a march tune on the piano, the Captain turns a simple dance into an obsessive, boot-stomping tarantella.

That scene was the climax of Olivier's frightening, overwhelming performance, but McNally doesn't shirk it one iota, any more than he ducks out of the heart attack that follows immediately. Olivier was coarse-grained, but icily calculating, too, whereas McNally is more blundering and simple-minded.

He lurches out of the tower to go drinking down in the town with old comrades, "cannibalising" Kurt's son by signing him up, threatening Alice with divorce and a replacement, cursing the unseen daughter who is badgering him about his drinking. And at every turn, the actors find the grim comedy in the absurd extremity of the domestic fracas.

Indira Varma is perhaps too beautiful and insufficiently worn down for the role, but the years of abuse and beating have made her Alice harsh and resolute. In the first years of the 20th century, when the play was a sensation across Europe, this portrait of a marriage - raw, ridiculous, unforgiving - was unprecedented in the theatre, and it still retains its power to shock.

In the close confines of the smaller of the Trafalgar Studios, it's like being in the coffin itself with the Captain still twitching while Alice and Kurt - briefly reunited in a passionate encounter - hang around patiently to apply the last rites. Amazingly, and inevitably, too, they decide for the umpteenth time to blot out the past and go on living. And that's the biggest joke of all.