Alicia Berenson is a famous painter married to an in-demand fashion photographer, living in a posh area of London. One evening, her husband Gabriel returns home late. Alicia shoots him five times in the face and then never speaks another word.

This is a story of right and wrong, and how sometimes they look the same. 1926. Tom Sherbourne is a young lighthouse keeper on a remote island off Western Australia. The only inhabitants of Janus Rock, he and his wife Isabel live a quiet life, cocooned from the rest of the world. One April morning a boat washes ashore carrying a dead man and a crying infant - and the path of the couple's lives hits an unthinkable crossroads. Only years later do they...