Don Winslow of the Navy #58

Don Winslow finds himself sinking into a submarine after it is destroyed, and he discovers movement inside the wreck. He manages to escape and surface, tapping out a message on the hull to signal his survival. After being rescued by his companions including Bixby, Winslow and the crew are stranded on an island where their ship was also destroyed. They plan to build a fire for a signal and attempt to sleep, but Winslow stays alert through the night, suspecting trouble from a mysterious man with a sling whom he keeps watch over.