Imaginary friends should be a comfort when other consolations fail. But what if these longed-for companions think differently? What if they're none too pleased with those who have summoned them? What about other daydreams and nightmares? Is it so comforting to think that something eerie half-glimpsed in a shadow might actually be there?

Few of the River Kingdom's people realise there's an unseen realm alongside their everyday world. A realm where imagination can give creatures of make-believe and myth form and substance. A realm from which dangerous creatures can sometimes escape....