Readable first novel of sea-adventure and domestic soul-searching set convincingly on Hatteras Island, N.C., in the final year of WW I. The Hatteras Islanders, a close-knit community descended from pirates, rumrunners, castaways, and mutiny-survivors, are reduced to conflict among themselves when a stealthy German U-boat harasses their coast and the shipping lanes offshore. After commercial fishing, the main calling for Island men is the time-honored keeping of the Hatteras Light and the heroically vigilant manning of its US Life-Saving Station. When the German sub (emblem of a new and frightening kind of warfare) sinks first an oil tanker, then a lightship (using the Hatteras Light to keep its bearings as it hides in the shoals), and finally a ship with troops aboard, the Islanders are alarmed, then outraged and panicked--to the point that a conspiracy arises among those who want to do the unheard-of: extinguish the lighthouse in order to ""blind"" the sub. Malcolm Royal, keeper of the light, will never allow this, and a showdown finally comes in the life-long rivalry between Malcolm and his brother, Jack Royal, leader of the conspirators. On one mad and suspenseful night the light flickers, then is restored, the sub is destroyed, a second troop ship is saved, and other plots are deftly coiled up: a cocky US Navy lieutenant, Halstead, is chagrined; a third Royal brother, Harvard-educated Keith, will succumb at last to the calling of the Island (though the woman who loves him will flee it); and the ""good"" German, sole survivor of the sub's end (and perhaps aid to its destruction), will live among the Islanders, mingling eventually among this strong-blooded population of ""refugees."" Heroism and adventure, salt air, and a skillfully suspenseful plot are solid hooks here, though the Conradian high significance that the author makes claims for remains more strictly among the schools of the familiar fishes.