Everybody knew that a big fierce troll lived in the cave. "Leave me alone!" it yelled. So everybody did.

Only one child cannot turn their back on the troll at the edge of the playground. One day, he takes his chalks up to the mouth of the cave. He draws a flower with every petal coloured in but one, and leaves the chalk behind. The next day, the flower has been completed. Day-by-day, the boy and the troll finish each other's drawings, until they each draw a portrait, showing a boy holding hands with a fierce, scary troll. "But you're not a troll," says the boy. "You're a boy - just like me."

Patience, kindness and the power of art win out in the end: the two boys wordlessly draw together. Soon all the other children gather to join in with the game. Everyone forgets that there was a troll inside the cave. Because outside the cave, there is so much to draw.

This touching story shows the power of kindness, art and imagination, in the face of isolation and difficult emotions, and delicately embodies the philosophy of art therapy. From the creative duo behind A Shelter for Sadness, award-winning artist David Litchfield's illustrations bring life and colour to this gentle tale of hope and friendship by Anne Booth. The beautiful, textured illustrations are also a joyful celebration of pavement art that is sure to have little ones reaching for their own chalks.