The iron sickle

The head of the 8th United States Army Claims Office in Seoul, South Korea, is brutally murdered by a Korean man in a trench coat with a small iron sickle hidden in his sleeve. The attack is a complete surprise, carefully planned and clinically executed. How did this unidentified Korean civilian get onto the tightly controlled US Army base? And why attack the claims officer--is there an unsettled grudge, a claim of damages that was rejected by the US Army? Against orders, CID agents George Sueño and Ernie Bascom start to investigate.