Dr. Peter Blood, unjustly convicted of treason and exiled from England, becomes a notorious pirate.

When half-breed Indian Yaqui Joe robs an Arizona bank, he is pursued by dogged lawman Lyedecker. Fleeing to Mexico, Joe is imprisoned by General Verdugo, who is waging a war against the Yaqui Indians. When Lyedecker attempts to intervene, he is thrown into prison as well. Working together, the two escape and take refuge in the hills, where Lyedecker meets beautiful Yaqui freedom fighter Sarita and begins to question his allegiances.

The film pivots around the local Norwegian doctor and his family. The doctor's wife (Ruth Gordon) wants to hold on to the pretence of gracious living and ignore their German occupiers. The doctor, Martin Stensgard (Walter Huston), would also prefer to stay neutral, but is torn. His brother-in-law, the wealthy owner of the local fish cannery, collaborates with the Nazis. The doctor's daughter, Karen (Ann Sheridan), is involved with the resistance and with its leader Gunnar Brogge (Errol Flynn). The doctor's son has just returned to town, having been sent down from the university, and is soon influenced by his Nazi-sympathizer uncle. Captain Koenig (Helmut Dantine), the young German commandant of the occupying garrison, whose fanatic determination to do everything by the book and spoutings about the invincibility of the Reich hides a growing fear of a local uprising.

Soldier of fortune, Monroe Bieler, is sent to dole out some American-style justice when the wife and child of an African president are kidnapped by terrorists.