Classicly

The Double Life is a spirit possession fiction work by Gaston Louis Alfred Leroux, a French journalist and author of detective fiction. In the English-speaking world, he is best known for writing the novel The Phantom of the Opera.

Excerpts:

THE strange adventures of M. Théophraste Longuet, which ended so tragically, originated in a visit to the prison of the Conciergerie, on the 28th of June, 1899. Therefore this history is modern; but the writer would say that, having read and examined all the papers and writings of M. Théophraste Longuet, its recentness does not detract from its sensational character.