Gunned-down Dr. Eric Mercer's corpse was left in the street. His godfather, mob don Dino Scarpella, who became Castle's friend while advising on a crime novel, financed the doc's med school and enjoyed his 'discrete' medical services for wounded gangsters, only holds back on a precipitous gang war if Castle promises to crack the case as unrelated fast. Possible motives include internal mob power struggle, infidelity, and a Romeo and Juliet-secret involving Dino's daughter Jane. Esposito grudgingly agrees to pose as ex Lanie's fiancé during a rare surprise visit from her parents, which proves harder than expected, but also more revealing.
—KGF Vissers