Grandpa is dying. He can barely move his hands any more but, stubborn as ever, refuses to stay in hospital. He's determined to finish his last painting, 'River Boy', before he goes. At first Jess can't understand his refusal to let go, but then she too becomes involved in the mysterious painting. And when she meets the river boy himself, she finds she is suddenly caught up in a challenge of her own that she must complete - before it's too late . . .