Blood On The Arch <\b>($22.95; Apr. 256 pp.; 0-312-24179-8): The Gateway Arch, that is, and yes, Mark Drucker left his bloody handprints all over it while he was being battered to death. Now it’s up to Detective Joe Keough (In the Shadow of the Arch, 1998, etc.) to figure out who wanted to stop political aide Drucker’s political plans enough to kill him—even though Keough will soon be reeling from the punishing news of his own diagnosis with adult-onset diabetes and a death that strikes a lot closer to him than Mark Drucker’s.