Although praise was heaped by most critics on Ian McKellen's King Lear at its Stratford premiere in June, I remain unconvinced of its greatness and unmoved by its performance.

An actor of outstanding intelligence and a versatility few of his contemporaries manage to muster, I thought McKellen would easily slip into the old, royal robes and not shrink from facing the trials of this Mount Everest of roles. Yet the spiritual journey undertaken by his Lear proves no more profound or adventurous than a jovial, charity jog, in which the heights of Primrose Hill are scaled to benefit Help the Aged's campaign to publicise the trials of old age.

The high emotional states of rage, outrage and grief through which Lear passes on his road to self-discovery are registered by Sir Ian in a low-key, flatly delivered, sentimental performance that tends to restrict Lear to doddering affability and charm, with second childhood fury shading into the twilight world of senile confusion. As a result of this clever, technical acting, the elemental moments of "Howl" and "Never" carry no tragic resonance.

It is no surprise that William Gaunt's fine if over sonorous Gloucester rather than McKellen's Lear manages to wrench the heart: blind and demoralised he lies in the king's arms, emitting strange, dreadful sounds of grief.

Trevor Nunn's production literalises Lear's reference to "this great stage of fools" by presenting the play within the decayed framework of a maroon-curtained dress circle, supported by scaffolding, which collapses as Lear's kingdom does. This conceit has already been better used in Jonathan Kent's Almeida production of the same play.

When this Lear first appears, to the accompaniment of tumultuous organ music, the courtiers abase themselves as if the king were an ancient God-head. The king though is adorned in the military scarlet and gold of Upper Ruritania, redolent of the 19th century.

In Nunn's hectic cul-de-sac of a no man's land the cruelty turns melodramatic - Sylvester McCoy's grotesque Fool is seen hanged. Yet Philip Winchester's Edmund transmits no serious evil while Ben Meyjes reduces Edgar to repetitive strain hysteria. At least Guy Williams's Cornwall betrays a genuine, chilling brutality that chimes with the elegantly conveyed malevolence of Frances Barber's sexed-up Goneril and Monica Dolan's sadistic Regan. If only McKellen's Lear could unlock his shuttered heart.

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