A SERIES of wooden packing cases stand on the Playhouse stage.

The first door opens, beckoning you inside and your journey in an anxious youngster’s footsteps begins.

He’s a 15-year-old boy who likes numbers but struggles with words, misses his elder brother and can’t understand why his parents are behaving so strangely.

Mark sees the world in his own very special way. His older brother is in the Army now, but just before he went to the desert he told Mark to look after his prized marbles. And Mark can’t find them any more.

He wants you to help him find his lost marbles and to do so you have to follow him from wooden box to wooden box, discovering the different rooms and memories within.

This ingenious piece of theatre is aimed at children, but it doesn’t pull its punches.

The subject matter of loss and grief is difficult for all ages to deal with, and here it does so in a unique and compelling way that is sure to enthral younger theatre visitors.

With strong characterisation and an intriguing plot, theatre company Slung Low has hit on a method of story-telling that they’d be smart to patent.

Laura Davis