Lloyds of London hires Jim Landers to investigate Captain Machen and find out whether or not he is scuttling his ships to collect insurance money. In order to avoid suspicion, Landers allows himself to be shanghaied aboard the Dorothy Low on her next voyage where he discovers the brutality of First Mate Erickson. Despite the brutality on board, Landers remains skeptical of accusations of scuttling because Machen has brought his daughter Laura on the voyage. However, the ship is scuttled en route and Erickson dies. Machen, Laura, Landers and some crew members survive, but Machen is critically injured and, on his deathbed, confesses that he had previously scuttled a ship because it was carrying arms to Mexico. The case satisfactorily resolved, Landers realizes that he has fallen in love with Laura.