There’s not much light in the story of a 13 year old boy watching his mum die of cancer. But, in Sally Cookson’s devised adaptation of Patrick Ness’ children’s book, there are many moments of piercing, gutting beauty.
Cookson’s previous literary adaptations – Jane Eyre , Peter Pan , The Lion, the Witch and the Wardrobe  – have used playful, messy, homespun theatrical forms to enhance the act of storytelling.
A Monster Calls is strongest when it comes to exploring depths of emotion. It’s frequently heart-rending and painful. But that playful theatricality is less thrilling here than in her other productions.
In Ness’ book a giant yew tree visits Conor O’Malley at night and tells him dark stories as he tries to cope with his mother’s decline. The obvious challenge for a stage adaptation is the tree. In the rehearsal room Cookson’s company  struck on the idea of creating it using tangles of thick rope with an actor suspended in the middle.
Although it’s cool to see the ropes twist into life like tendrils, and despite Stuart Goodwin’s performance as the tree, bare-chested and booming, mostly it doesn’t quite have the impact it should. It’s too human and half-formed, which detracts from its grandeur and ferocity.
In other places the production gets bogged down with long patches of movement and montage on the bare white stage, which interrupt the flow of the story more than they aid it.
Not that it matters, not really, not when Matthew Tennyson plays Conor so perfectly. His awkward, wide-eyed mannerisms, the way he walks around with a drooped head, like he wants to disengage from the world, his hands fidgeting at his sides – it all comes together to create this lost and lonely teenager full of anger and guilt.
There’s also an amazing moment when his annoying grandmother, captured brilliantly by Selina Cadell, walks back into her house completely knackered from staying by her daughter’s bedside and finds that Conor has wrecked the place.
That moment, and a few others like it, bring horror, grief, rage and so many other conflicting emotions into a distressing unity.
A fantastic soundtrack by Benji Bower performed live, awash with strange harmonies on top of electronic beats, underscores the trauma of the piece.
Ness’ story offers no resolution, and no easy escape. It invites us to embrace the fact that grief is complicated, full of paradox, and unending.
It’s that message that carries the show, more so than its visuals or its aesthetic. The power of the story being told is considerable – it’s a wondrous thing.