It's the latter half of the Roaring Twenties and Lady Lucy Revelstoke, the unconventional widow of a young British lord, is once more crossing the Atlantic on a state-of-the-art ocean liner. Rubbing elbows with the era's elite, Lucy has come a long way from her roots as the daughter of a Canadian mobster.

But when a dead man turns up in her stateroom on the first night of the voyage, Lucy wonders if her past has come back to haunt her. Who is this dead man? Is someone from her past trying to send her a message? Lucy doesn't wait to find out. With her chivalrous friend Lord Tony, and Elf, her pickpocket-turned-maid, she endeavours to throw the body overboard. It does not go as planned.

When the body is discovered by authorities on the ship, Lucy must do everything in her power to find the murderer before they look too deeply into her past.