German Leopold von Ragastein meets his doppelganger, Englishman Everard Dominey, in Africa, and plans to murder him and steal his identity to spy on English high society just prior to World War I.

However, doubts of the returned Dominey's true identity begin to arise in this tale of romance, political intrigue, and a (literally) haunting past.

Princess Stephanie Eiderstrom believes at first sight that Everard is actually Leopold and threatens to expose him unless he agrees to a rendezvous with her.

Seaman and reveals that Leopold had been banished to Africa for killing a Hungarian prince, the husband of his lover Princess Eiderstrom.

Seaman, in turn, tells Everard that his mission is to monitor the German Ambassador, Prince Terniloff.

He refuses because it would reveal his identity and because he loves Rosamund, who just returned from the mental hospital after ten years away.

Everard and a hunting party explore Black Wood and find that the ghost has left tracks.

Everard accuses her of driving his wife to insanity, creating the howling ghost of Roger Unthank, and victimising an attempted murderer.

Seaman and Schmidt are arrested, Eiderstrom leaves in disgrace, and Everard is left with his wife, who now acknowledges him as her true husband.

The political intrigues of the novel – the initial spy mission for von Ragastein, the fights between Mr.

Seaman and Duke Henry, and the presence of Ambassador Terniloff, among others – are focused entirely on the struggle between the British and the Germans, with Great Britain as the "good" side and Germany the "bad" one.

Roger Unthank goes to Black Wood after a traumatic event, and returns years later a crazed man.

Both Lady Dominey and Princess Eiderstrom propose, at various points during the impersonation, that their true lovers were left behind in Africa, and what returned is a false similarity.

The book was so popular in its time that it sold over 1 million copies in 1920 alone, and was the 8th best-selling novel of the year in the United States.

The last was in 1942, and has significant plot and name changes (mostly to set the story in World War II), Ralph Bellamy stars as Edward Dominey/Leopold von Ragastein, and it is directed by John Rawlins.