In 1908, on the inaugural journey from Europe to the United States of the world's first underwater railway, seventeen-year-old Rosalind finds love, a murder mystery, and the truth behind the railway's construction.

In 1908, on the inaugural journey from Europe to the United States of the world's first underwater railway, among the passengers are Rosalind Wallace, her friend Cecily de Vere, and Cecily's brother Charles. When Charles disappears on the station platform Cecily doesn't seem concerned about her brother. And when Cecily runs into an old friend onboard, another belle of the European aristocracy, she appears to forget about Charles altogether. Then, deep under the Atlantic, Cecily and her housemaid, Doris, are found stabbed to death. Rosalind is now trapped in a deadly fight to clear herself of her friend's murder and to thwart a sinister enemy whose ambitions she can only imagine.