In keeping with Nicholas Hytner's refusal to play safe with the musical genre, this collaboration between Tori Amos and the dramatist Samuel Adamson – brilliantly staged by Marianne Elliott – is a ravishing fusion of theatrical arts.
Giving a feminist twist to a Victorian fairy tale by George MacDonald, it's a darkly droll coming-of-age piece that focuses on the heirs to two kingdoms and their reactions to grief.
Princess Althea takes refuge in a perverse weightlessness; Prince Digby copes with loss by becoming a solemn soldier.
Rosalie Craig pours forth a stream of glorious sound, Amos's score is richly textured, and Rae Smith's designs have a delectable wit. Bewitching.
(020 7452 3000) to 9 January