The setting of the novel is Shanghai, China in early 1941 , before the onset of U.S. involvement in the hostilities known as World War II. We are first introduced to corporal Kenneth McCoy , a bright 21 year old Marine who has just "shipped over" for a second enlistment in the Marine Corps. After McCoy defends himself from the assault by a group of Italian Marines , by skillful use of a knife , he becomes known as "Killer" McCoy. Captain Edward Banning enters the series as the intelligence officer of th 4th Marines assigned to help McCoy as his defense officer at a Court Martial for killing the Italians. After "Killer" McCoy is cleared , Banning enlists Ken as an assistant in collecting intelligence on the Japanese army that is occupying China. Sergeant Ernest Zimmerman is a motor pool NCO who operates convoys to various Marine installations in the vicinity of Shanhai ; McCoy is subsequently assigned to the convoys to collect information for Banning , using his lowly status for cover. The Japanese provoke another incident wherin McCoy kills a number of "Chinese baandits" with Zimmerman , which results in his transfer back the the U.S.
Unbeknownst to McCoy , he was selected by Captain Sessions , who met Ken on the convoys ,to be run through an officers's course at Quantico. While at Quantico, Ken meets Malcom "Pick" Pickering who continues to play a major role in later novels, as well as his romantic interest in the person of Earnestine "Ernie" Sage.