You don't find out why the whales came until right at the end of Theatre Alibi's excellent adaptation of Michael Morpurgo's novel, which is set on the Scilly Isles during the first world war. But the reason is well worth waiting for in an evening of thrilling theatre that is taut and suspenseful, and manages to evoke childhood and a bygone era without wrapping the whole in a blanket of nostalgia.
Idyllic freedom and terrible hardship walk hand in hand for young Gracie and her friend Daniel. When Gracie's father joins the navy and her mother falls sick, the child doesn't get enough to eat, and Daniel lives in fear of his ignorant bully-boy brother, big Tim. As in the best stage adaptations, the raw material is very good. Greg Banks fillets it very well to create the storytelling skeleton that he and co-director Nikki Sved flesh out to great effect on Dominic Hooper's atmospheric set.
With its bleached hues, the latter cleverly suggests boat, whale and house as well as all the debris of a seashore awash with flotsam and jetsam. The cries of circling gulls add to the eerie sense of remoteness. The playing style is very simple - the precariousness of the children's misadventure on a foggy sea at night is brilliantly evoked with a seesaw plank of wood - and a comic interlude in which the islanders get the better of the law is ingeniously handled. Big themes - in particular shame and redemption, ignorance and prejudice - do get a look in, but the piece never loses sight of the fact that it is telling a story to entertain.
Like all the best stage adaptations, it doesn't make you feel that you've "done" the book, but leaves you wanting to return to it afresh. If the West End could only offer more family-friendly theatre like this - and not just at Christmas - it would be a far nicer place.
· Until January 7. Box office: 0870 060 6622.
