You Only Hang Once, first published in 1944, is a noir murder mystery featuring private-eye Sid Ames and public-relations man Johnny Knight, who discovers a dead lawyer in his office. Ames, who has a predilection for alcohol, is hired to investigate the murder, and along the way, two additional murders occur, plus blackmail and thieves fighting over a packet of diamonds. Author H. W. Roden (1895-1963) was an author of mystery-thrillers; You Only Hang Once was the first of four books featuring Sid Ames and Johnny Knight.