Knowing that he is dying, Jess's grandfather insists on returning to the river he had known as a boy to finish a special painting and fulfill a life-long dream. Jess is training to be a long distance swimmer, so when Grandpa is napping, she practices in the river. But soon, she starts seeing a presence there -- one that is also affecting Grandpa's painting. Who is the boyish figure Jess sees in the river? What does he want her to do?