A boy is found, moments from death, and taken in by a kindly family. Gentle, precocious, talented, he flourishes in his new home, and the family show him a life he hadn't dreamed possible. But he refuses to speak a word, or reveal a single detail about who he is. As he grows into a young man, falling in love and taking classes at the prestigious Conservatoire de Paris, he can almost forget the terrors of his past, or the promise he has made. But in 1930s Europe, an evil is rising across the continent and no one's safety is certain. In his heart, he knows the time will come where he must flee once more. All the seven sisters are gathered for the first time, on board the Titan to say a final goodbye to the enigmatic father they loved so dearly. To the surprise of everyone, it is the missing sister who Pa Salt has chosen to entrust with the clue to their pasts. But for every truth revealed, another question emerges. The sisters must confront the idea that their adored father was someone they barely knew. And even more shockingly: that the secrets of his past may still have consequences for them today. Spanning a lifetime of love and loss, crossing borders and oceans, draws the series to its stunning, unforgettable conclusion.