Walter Huff is a 34-year-old insurance agent working for General Fidelity in California. It is implied that Huff had never committed a serious crime before meeting Phyllis and was well-behaved. As a seasoned agent, Huff is in a unique position to game the system and commit fraud. He is the narrator for Double Indemnity, which is framed as a confessional he recorded after committing his crimes.

Walter Huff is the archetypal corrupted agent of an organization, doomed to calamity because of Temptation and the Femme Fatale’s seductiveness. Much of the novel takes place at night and Huff spends most of it in the dark, whether he is lurking outside waiting to kill Nirdlinger or in bedroom panicking over his fate.

Huff’s dark surroundings symbolize his corrupted nature; the few moments he has in the light suggest the good man he once was. Huff is notably in the light when he realizes he loves Lola and when he kills himself due to crushing guilt.

Phyllis is the femme fatale—French for “deadly woman”—of Double Indemnity. The femme fatale is a literary archetype, or stock character, and an important trope in crime fiction. The femme fatale expresses unrestrained sexuality and has an almost-magical power to seduce men.