Murdoch and Inspector Brackenreid are aboard the SS Keewatin after the owner, Clarence MacFarlane, receives what he believes is a threat. The Keewatin is about to depart from Toronto on its maiden voyage destined for Rochester, N.Y. and Murdoch thinks they should stay on board, especially after he sees that Julia is one of the invited guests. Their presence proves useful after MacFarlanes daughter Amy, who is engaged to her fathers chief financial officer Owen Mathers, falls overboard and is nowhere to be found. As Murdoch investigates he finds there is a real threat against the Keewatin and the true facts behind Amys disappearance. 故事背景是发作在1895的加拿大，主人公默多克是个年轻俊秀的侦探，他的破案手腕在当时看来都是非传统的，但却破获了一宗又一宗案件，他的上司固然对他破案手法嗤之以鼻，但每次破案后又对本人有这么一个下属感到自鸣得意，但病理学家却对默多克的破案手法很是观赏，同时为他破案也提供很多协助，而默多克也对她日渐留恋，但又难以启齿。