I too enjoyed this book and have not seen the film - but can see that it would make a good film. This was the review of it that I wrote for local magazine:
The Light Between Oceans by M.L. Stedman
M.L.Stedman was born in Western Australia, but now lives in London where she worked as a lawyer. As far as I can see The Light Between Oceans is her only book.
Set in the months after the First World War, the novel traces the life of Tom Sherbourne, a much decorated young veteran who chooses to find work as a lighthouse keeper on the uninhabited island of Janus, where he hopes the solitude and strict routine will help him to come to terms with his harrowing memories. Essentially an upright honest man he struggles to reconcile the dilemmas of war, where evil actions result in praise and admiration.
On leave on the mainland he meets and quickly marries Isabel – the headstrong charming and loving daughter of the local school headmaster. Their life on the island is in many ways idyllic – they thrive on the proximity of nature, and settle happily into their strange isolated existence. But this idyll is marred by a series of miscarriages and a stillbirth. Whilst grieving for their lost children they are one day faced with the arrival of a boat washed up on shore and containing a dead man and a live baby. Isabel immediately takes this child to her breast and persuades Tom not to report what happened. Lucy, as they name the baby, rapidly steals her way into both their hearts and she grows up happily on the island with Tom and Isobel as her father and mother. The remote environment of the island, both physically and morally, makes it possible for Isabel to justify their actions, but Tom suffers a daily battle with his conscience, in spite of his deep love for the child and his joy at seeing Isabel thrive as a mother.
Stedman's writing is seductive – we are drawn into agreeing with actions that we know to be unwise and immoral; and faced with conflicting sympathies. It is a story of what happens when good people make bad decisions.
One of the most interesting characters is someone we never meet: a young German man who is persecuted by the Australian locals but is determined not to let this make him bitter:
"You only have to forgive once. To resent, you have to do it all day, every day. You have to keep remembering all the bad things."
This is an exquisite and moving book – I cannot recommend it too highly.