Macbeth, Almeida, London

The director Travis Preston's concept is, in theory, attractive. So much of the first two-thirds of the play seems to take place inside the hero's head: afterwards, as we lose this close relationship with him and he becomes a punch-drunk, desensitised brute, the drama itself arguably relinquishes some of its grip. Why not maximise the tragedy's strengths and disguise its unevenness by presenting the entire work as the emanation of the protagonist's haunted brain?

That would be fine if you got a shuddering sense that the story and its characters had taken psychic possession of the performer, as you did when Fiona Shaw delivered her one-woman Waste Land, a kind of spooky controlled identity crisis. Preston's production does not make the mistake of Robert Lepage's Elsinore, a solo version of Hamlet that buried the play under of a box of wizardly tricks. It's wisely low-tech - just Dillane, barefoot in a grey lounge suit, cutting a sensitive, wary figure as he stands, crouches and crawls on a dirt floor, to the live underscoring provided by three musicians.

The trouble, however, is that a lot of it is unwisely low-key. It starts not with the witches and the thunder and lightning, but with the King's first line: "What bloody man is that?" The Weird Sisters' prophecies are intoned in a sing-song, almost perfunctory manner, as though this way of objectifying the hero's desires is just an embarrassment to be whipped through as quickly as possible. The power of the external influences operating on him is underplayed. Rather than a force to be reckoned with, Dillane's Lady Macbeth is a patronising travesty of the woman: coy, effeminate rather than female, with a puzzling penchant for lapsing into French. Her hold over him appears to be the most simplistic form of feminine wile. You can't see why the hero would ever have been in awe of her masculine resolve and ordered her to bring forth men children only.

The actor achieves split-second shifts between characters (deep-voiced for Macduff; nervously stammering on the letter "M" for Malcolm), but, even when leaping into the audience during the banquet scene, he fails to generate the requisite degree of horror and waking nightmare. Invisible blood could be made more unnerving in the mind's eye than dripping stage gore, but that's not the case here. There are also niggling logical difficulties to treating the play as a poem radiating from an individual consciousness. In what sort of afterlife are we to imagine Macbeth if he now has been made privy to the long English scene in which Malcolm subjects Macduff to a moral test?

True, Dillane, stripped down to a filthy vest, offers a blackly ironic take on the hero's coarsening. There's something offhand and bleakly flip about this burnt-out case, prone upon a pillow made by his jacket and shirt. And it's true to the nature of the piece at that point to have a morally exhausted Macbeth incredulously peering at the monster he has become. But too much of the play comes across as a set of sardonic variations in search of a main theme. It's perverse that an exercise that should have pulled us inside the hero's head leaves us so often feeling emotionally distanced and disengaged.

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