Dr. Mark Muir, a young American metallurgist, persuades American tycoon JP Morgan to hire him for the biggest shipping project the world has ever seen: RMS Titanic, at the Harland & Wolff shipyard, in Belfast. The shipyard's visionary Chairman takes the young scientist under his wing, introducing him to Belfast's Protestant elite. Mark quickly catches the eye of the charming, albeit spoilt, daughter of a magnate: Kitty Carlton. But he is also intrigued by a very different woman; Sofia Silvestri, an immigrant's daughter. Belfast, seen through Mark's eyes, is a city ridden with divisions of class and religion, from which, as a stranger, Mark should be far removed. But we soon discover that Mark is a man with a past mysteriously connected to the Catholic suburbs of Belfast.

The Admiralty has opened an inquiry into the Olympic accident, and Pirrie, Andrews, Morgan and Mark are invited to London. Mark is pleased to see his old friend Kitty, who has become a star. At the inquiry, the First Lord of the Admiralty, Winston Churchill, suggests that the yard could serve several ends in case of military escalation. Joanna Yaeger, Mark's old friend from New York, and Morgan's protégée, is forced into a very dangerous position: a spy. With her unparalleled access she can prove to be extremely useful to the Austro Hungarian and German causes. Back in Belfast, Mark faces a new crisis. Andrea, Sofia's old fiancée, has seen her with him and has told Pietro. Sofia is forced to choose. Sofia stays Mark. Finally he agrees to follow Sofia: they will move to London, together. He will leave Harland & Wolff and all hopes to ever find his own daughter. In a breathtaking ceremony, the Titanic is finally launched.

An accountant from the United States, Samuel, makes Mark feel jealous. Samuel is handsome and witty. He is American and unaware and uninterested in divisions. For Sofia, he represents a real temptation: Pietro is better and Mark still can't leave his job. Mark is still uncertain: he still hopes to find his daughter. Mark discovers what the girl's name was: Sarah. The girl might live in a small village outside Belfast. But the girl, who had indeed been living there, has left. They have moved to Belfast but no one knows where. Andrews fights, and looses, a memorable battle to equip Titanic more life boats. And while Pirrie and Churchill try to campaign for Home Rule in Belfast, the divide between the Catholic and Protestant communities has grown. Lord Pirrie, by now disillusioned with most of his liberal principles, falls ill.

The time has come for the great ship to leave for the New World. As Morgan always wanted, Titanic's maiden's voyage will become one of the first great PR events. Sofia and Joanna Yaeger are friends and she gets her a job as an illustrator for the New York Times. Pietro uses most of his money to buy her a ticket. Mark himself only gets on board by chance. The group also includes Jack Lowry, a young riveter we met since the beginning of the story. Violetta with the baby, whom Michael MacCann, has come back to marry. Joanna will be onboard – and so will Kitty, by now an acclaimed actress. A little girl by the name of Sarah, with her mother, will board Third Class. Neither Mark nor his daughter are aware of their presence onboard the Titanic. And, while the ship sails for New York, and Mark and Sofia finally find happiness and reconciliation, we are left asking ourselves: who amongst our characters will survive the great disaster?