Present day: For years Shelly Summer has buried herself in her work, trying to forget her past. The only time she feels truly herself is when she's diving in the Mediterranean - the calm and stillness of the clear waters help her forget.

When Shelly stumbles across her great-grandmother's belongings she starts to uncover secrets which might help her let go of her past...

1916: When trainee nurse Gertie Smith signs up for the war effort, she heads to Greece with a head full of blue skies and handsome men. Unprepared for the horrors of war, she boards the Titanic's sister ship, the ill-fated hospital ship Britannic. Tragically, the Britannic never reaches its destination.

When rescued, Gertie is taken to the Greek island of Kea, where she falls in love with a Greek fisherman, Manno - but she finds herself torn between him and her duty to an English soldier...