"I am here, but I am not all there." So declares the troubled monarch at the centre of Alan Bennett's play. In Christopher Luscombe's production, a wall of empty frames looms over the stage: this royal family is expert in framing itself for public view. But now, someone has forgotten how.
Bennett's play follows the illness which gripped George III in 1788 (now thought to be porphyria) and the politicking and absurdity which arose as a result. At its centre is David Haig's irrepressible King. He whizzes from person to person like an over-wound top: well or ill, words gush from his lips. During the illness the words threaten to overwhelm him: his head lolls helplessly in an attempt to follow his own babble. He is childlike, lifting his knees in glee at a good joke – and vulnerable. As his Majesty is forcibly strapped into a chair, dressed only in a nightgown, his legs bandaged after medicinal blistering, it would be a hard heart that was not moved.
A heart as hard, perhaps, as that of Dr Francis Willis, played superbly by Clive Francis. Willis is called in when the King's fleet of doctors fail him. Despite the stern looks, the strait jacket and the restraining chair, the audience – like the King – can't help but admire this bluff Lincolnshire parson. The other doctors, by contrast, are pompous, privileged prats. Peter Pacey, Madhav Sharma and John Webb clearly relish their cartoonish parts, although the caricatures do begin to grate.
The leader of this beau monde is Christopher Keegan's brilliant brioche, the Prince of Wales. He swaggers, giggles, sticks his nose in the air and puffs his chest out until you're afraid he might pop. His mother, Queen Charlotte, played by Beatie Edney, is similarly enormous – in girth, hair, dress, yet also in affection and loyalty to "Mr King".
The best moments come from Haig: as he reads King Lear, becoming aware of the irony; or when he pleads with beautiful Lady Pembroke (Charlotte Asprey) "Did we ever forget ourselves? Because if we did, I would so like to remember."
Luscombe's production and Janet Bird's design are infused with Georgian elegance and refinement, but the evening's triumph is to show the fragility of this china world, which has a bull at its centre.
To 3 September (01225 448844); then touring to 14 November; for dates, see www.theatreroyal.org.uk