Celebrating the end of exams with best friend Grace, 17-year-old Alex rescues a swan caught on a wire in the Thames mud and finds an extraordinary bracelet.

She discovers that she can use it to communicate with the river's dead.

Condemned to a half-life of misery, they must steal the happiness of the living to exist.

Callum - desperate, lonely and breathtakingly good-looking - is one of them.

Alex falls deeply in love.