From the moment Nancy Drew boards an ocean liner leaving for New York, she becomes involved in a new and dangerous mystery.
A man on the pier gestures to someone on board in sign language: “BEWARE OF NANCY DREW AND NE,” he signals.
Who is NE?
Can it be Nelda Detweiler, a young woman who shares a cabin with Nancy, Bess, and George?
Mystery and intrigue follow the girls across the ocean; but with her usual ingenuity, Nancy solves the mystery and defeats her enemies before the ship reaches New York.