Hamlet, Old Vic, London

To have discovered one striking young Hamlet for our times might be considered good fortune. To have discovered two - for the same production - begins to look like a stroke of genius.

To have discovered one striking young Hamlet for our times might be considered good fortune. To have discovered two - for the same production - begins to look like a stroke of genius. That, though, is what Trevor Nunn has accomplished in his modern dress version of the tragedy at the Old Vic. A few weeks ago, the 23-year-old Ben Whishaw opened in the title role to the acclaim of most critics, some of whom were moved to recall David Warner's famous characterisation of the Black Prince in the Sixties as a college-scarfed reflection of the nascent student disaffection of that era.

Three times a week, however - on a Monday evening and at the Wednesday and Saturday matinée - the role of Hamlet is played by another 23-year-old: Al Weaver, who, on other occasions, is the grave-digger's mate and the Player Queen. It's excellent to report that people who have tickets for these dates need feel, in no respect, short-changed. Weaver gives a wonderfully winning performance and it's remarkable how he avoids being a carbon copy of Whishaw.

Admittedly, the production's take on the character of Hamlet is, in my view, a restrictive one. There's nothing in the text to suggest that, before the twin blows of his father's death and his mother's remarriage, the Prince was not a brilliant, well-adjusted man. Here, by contrast, the gasping, snivelling grief and aggressively curled-up postures of the woolly-hatted hero suggest a pre-existing self-pity and alienation that have now found the opportunity for full tearing expression.

Within that limitation, Weaver works wonders. With his mop of Harpo Marx curls, skinny figure and lean, witty face, he's a very engaging presence and he has a suddenness and lightness of attack that make him very adept at the fleet, false-footing comedy with which Hamlet, in his antic disposition, twits the court. Though the vowel sounds are RP, there's a Northern undertow in Weaver's verse-speaking that heightens the sense of unguarded openness in his delivery of the soliloquies. If inexperience is occasionally betrayed by a tendency to portray emotional turmoil by hoarse decibel escalation, this actor has the essential quality needed: the ability to pull you into Hamlet's largeness of spirit and convince you that, in this play, Shakespeare was dramatising the world as (to use Keats's later description) a "vale of soul-making".

Imogen Stubbs is one of the finest Gertrudes I've seen. As she charts the Queen's decline (or is it her progress?) from an adoring, glamorous wifey-figure to a disillusioned realist taking comfort in the vodka bottle and recoiling in sickened reproof from Claudius, she brings astute psychological shading to a notoriously enigmatic character.

In her topple from sexy, superficially sophisticated schoolgirl to insane suicide, the stunning Ophelia of Samantha Whittaker is shown in moments that valuably flesh out her plight.

Far from being a Hamlet without the Prince, this is a Hamlet with two of them. Both well worth catching.