A long night's journey into the heart of Eugene O'Neill's drunken masterpiece

There's a moment late on in Laurence Boswell's excellent revival of Long Day's Journey Into Night when you wonder how much further into this night we can journey before dawn breaks. Either that or the bourbon will run out.

Eugene O'Neill's magnificent drink-sodden play, written in 1941 and first performed posthumously in 1957, receives the kind of harrowing, tortured performances that leave you an emotional wreck. That's by the interval. Two hours later, as the hefty fourth act nudges towards 11.10pm, compassion fatigue sets in. It's a shame O'Neill never saw it, he might have made some cuts.

"Here's to health and happiness," says the father, James Tyrone, played with ravaged, tyrannical charm by Richard Johnson, as he raises his whisky glass. In a dishevelled grey suit, and jutting out a bulldog chin, Johnson utilises all Tyrone's skills as a one-time successful actor to suppress anguish with bravado.

"That's a joke," replies Edmund, the younger son (Paul Rhys), twitching involuntarily, his reddened eyes standing out against his thin, sickly face. For the Tyrone household, as we discover, is a miserably sick one: Rhys has consumption, his mother is a morphine addict, the others drink themselves into oblivion. The cast capture this jittery, fevered household superbly: the Tyrones slug it out from morning to night, filling the bleached wooden living-room of the summer home - discreetly designed, in the round, by Peter Ruthven Hall - with sour truths and brutal recriminations that return as insistently as the foghorns out at sea.

The brittle, fatalistic Mary - hauntingly (and often wittily) portrayed by Penelope Wilton - tugs nervously at her necklace, delivers acid judgements, and stays resolutely in denial over her addiction. Her elder son James, an essay in ebullient self-loathing by Mark Lambert, is a Broadway loafer, whose ambition stretches as far as whisky and whores. Drunken acting quickly becomes dull, but as Lambert stumbles around the room his remarks stay woundingly in focus: he not only knows he is a failure, he knows he wants others to fail too. O'Neill's masterpiece is the worst advertisement for "family values" since the Greeks first told us about the House of Atreus.

A month after the dull, trivial romp at the Open Air, Regent's Park, we have a beautifully measured, carefully delineated version of The Comedy of Errors directed by Tim Supple, which plays at Stratford until September, then tours 16 venues until the spring. Catch it when you can. Supple's thoughtful treatment of Shakespeare's early comedy brings welcome emotional insight.

Comedy of Errors opens with 150 lines of what script editors would term "back story" from the Syracusan merchant, Aegeon: an opening which frequently embarrasses directors keener to get on with the comedy than dwell on the errors. Not here. Supple demonstrates that the errors to be righted are bigger than routine ones of mistaken identity.

As we enter the Other Place, the harried, weather-beaten Aegeon (Christopher Saul) sits in chains in a brick square. When the Duke (Leo Wringer) arrives, exuding a cool crisp authority in an equally cool, crisp uniform, he listens with absolute attention to Aegeon's wretched story of how he came to lose wife and sons, and pitch up in this hostile city. The comedy unfolds under the threat of his death sentence.

It's a mark of Supple's success that he draws us rapidly into a psychologically plausible world in the middle of so many coincidences. The designer Robert Innes Hopkins creates an attractively authentic Ephesus, where one main brick facade serves as the front for the traditional three houses of Plautine comedy. A bewitching musical accompaniment from Turkish string and percussive instruments, as well as plaintive Asiatic vocals from Sylvia Hallett, reinforce the exotic atmosphere of this sunbaked coastal port.

As another new arrival, Robert Bowman, playing Aegeon's son, the understandably wary Antipholus of Syracuse, skilfully registers genuine bafflement. He looks remarkably like the twin brother he has never met (Simon Coates), who already lives here. It's not just the matching suits, shirts, shoes and ties. It's the hairstyle. Both have thick curly brown hair brushed back, with trim moustaches and beards. Their twin servants, the two Dromios (Eric Mallett and Dan Milne), vigorous emphatic figures in linen jackets, T-shirts and baggy shorts, look similarly alike. They have shaved heads.

Anxiety powers the comedy: Coates's wife, the assertive Adriana (Sarah C Cameron), has genuine worries that her husband no longer fancies her, while her sister Luciana (a forcefully intelligent performance by Thusitha Jayasundera) indignantly rejects Bowman's advances , thinking he is her brother-in-law. Reactions throughout the evening are precise: when Coates hands back the diamond ring to the courtesan (Maeve Larkin, looking more like a Mayfair socialite than an Ephesian whore), he thanks her for her "good cheer", catches his wife stiffening with hurt, and bites his lip.

The ending, which might be pure corn, brings Aegeon's opening speech full circle. "Why here begins the morning story right" says the Duke. It brings, too, a rare sense of wonder: brothers separated from birth have been reunited, parents find their children, and a man facing death gets a reprieve. It's unexpectedly moving. After sitting grimly through the last three Shakespeares at Stratford, I'm happy to salute this one as first-rate.

The West End revival of Henry James's The Aspern Papers, adapted in 1959 by Michael Redgrave, shows how style dates faster than subject matter. In this sour, intriguing tale, a man insinuates himself into the Venetian home of an old lady and her niece, in order to obtain love- letters written by a famous poet. Henry James was prescient to spot the extent to which biographers and literary sleuths would invade people's privacy in the search for material.

Redgrave was less prescient, however, in his stagecraft. Bald exposition, melodramatic touches, curtain lines, an obligatory storm, and occasional hints that we might be straying into a Raffles or Sherlock Holmes plot, suggest that this adaptation might have been disinterred from the same trunk that contains the precious cache of letters.

As the literary critic, Daniel J Travanti, from Hill Street Blues, slyly mops his brow and enunciates his words with an odd deliberateness. Moira Lister gives the wheelbound old lady a defiant sense of her own grandeur, while Hannah Gordon, as the plain niece, Miss Tina, grows in emotional authority as the play progresses. These three cast a slow spell. For too much of the evening, though, I was siding with the old woman's argument that it was a mistake to rake up the past.

Theatre details: Going Out, page 14.