Jack O'Judgment is a 1920 thriller novel by the British writer Edgar Wallace. It features a vigilante who takes action against a gang of blackmailers, using a mysterious identity and leaving the Jack of Clubs as a calling card. Excerpt: "He looked at the thing in perplexity, for the fate of his erstwhile assistant had long since passed from his mind. Then he saw writing on the margin of the card, and twisting it sideways read: "JACK O' JUDGMENT." Nothing more! "Jack o' Judgment!" The colonel screwed up his tired eyes as if to shut out a vision."
