The Dungeon.

Myrtle Downing, an African-American woman, is coerced into marrying a corrupt would-be politician named Gyp Lassiter, even though she is really in love with Stephen Cameron, a young lawyer. When she discovers that her husband has conspired to support segregationist policies in exchange for support by white political power brokers, she objects to his crooked dealings and gets herself imprisoned in a secret dungeon where her husband had murdered his previous wives. Presumed to be a lost film.