Bleeding in the Eye of a Brainstorm — George C. Chesbro

Mongo's back in his 12th novel (after An Incident at Bloodtide). The martial arts expert, PI and former circus star who happens to be a dwarf relies a bit less on gymnastics and coincidence this time, and more on his human nature. On a cold night in Manhattan, against his better judgment, Mongo takes in homeless Mama Spit, who has suddenly become clearheaded and is anxious to abandon her former residence, a heating grate, and to pick up her former life as Margaret Dutton. Her cure was effected by some pills a young man pressed into her hands just before he was killed. As a side effect, Margaret's senses of smell and taste have been enhanced. Mongo discovers similarly enhanced senses in Michael Stout whom he encounters at a local chess club. From Stout, Mongo learns that a dozen patients at a mental hospital run by the Chill Shop, a covert CIA group, have escaped. All had been taking this unknown drug, a mixture "of heavy duty psychotropics," likely to cause death if abruptly withheld. To cover up the program and the escape, two assassins aim to eliminate the escaped patients and then Mongo, whose dogged pursuit of the villains creates a diverting mystery.