Flora Maguire, a young governess, is on her way home on the SS Minneapolis after the wedding of her employer's daughter. She meets the charming Bunny Harrington on deck on the first night and is conscious of her status among the first-class passengers. Flora finds the body of a man at the bottom of a companionway and when his death is pronounced as an accident, she is not convinced and is driven to find out the truth. Following a near drowning during a storm and a second murder, the hunt is on for the killer. Will Flora be able to protect Edward, her charge, as well as herself?