Jim is the 11-year-old son of a wealthy British family living in the International Settlement in Shanghai. Surrounded by a cultural environment that considers itself British, he often finds himself admiring the Japanese military and their stoicism instead. When the attack on Pearl Harbor throws Shanghai into chaos, his natural resourcefulness and independence are immediately put to the test.

Basie is an American sailor and former cruise ship entertainer attempting to survive the Japanese occupation of Shanghai. He possesses a natural charisma and relies on parlor tricks to distract and manipulate others. Highly pragmatic, he views the war as an opportunity to upend social hierarchies and advance his own interests.

Dr. Ransome is a British physician who attempts to maintain civility and structure during the collapse of the International Settlement. He values traditional British education and personal hygiene, actively working to arrest the descent into barbarism among his fellow prisoners. He attempts to provide a stabilizing, paternal presence for the displaced youth around him.

Jim's father is a successful British businessman living in the affluent Amherst Avenue area of Shanghai. He represents the comfortable, insulated world of the European expatriate community prior to the Japanese occupation. He is protective of his family and attempts to assist British sailors during the initial attack on the river.

Jim's mother is an affluent British expatriate living in Shanghai. She frequently tells Jim stories of her childhood in England, providing him with his primary connection to a homeland he has never seen. She represents the stability and comfort of Jim's pre-war domestic life.

Frank is a young American sailor hiding in the Shanghai shipyard alongside Basie. He is visibly unsettled by his circumstances and often falls victim to Basie's manipulative games. Though rough around the edges, he is noticeably more shocked than Basie by the brutal realities of their survival.

Mr. Maxted is a prosperous British architect who frequently attends the same social functions as Jim's parents. Accustomed to a life of Studebakers and casino gambling, he embodies the affluent lifestyle of the International Settlement. He serves as an alternative father figure whom Jim idolizes in peacetime.

Mrs. Vincent is a British internee trying to maintain a semblance of domestic normality under extreme duress. She is protective of her young son and often exhibits hostility toward Jim, though the older boys and men around her find her attractive.

Mr. Vincent is a British internee enduring the harsh conditions of the Japanese occupation. He attempts to carve out whatever privacy and dignity he can for his wife and six-year-old son in an increasingly crowded and desperate environment.

Mrs. Blackburn is an internee tasked with the difficult job of managing the meager food rations for the prisoners. She rewards those who assist her with chores, establishing a small economy of labor and fair food distribution.

Private Kimura is a young Japanese soldier assigned to guard the European detainees. He occasionally shows moments of leniency and shares his quarters or kendo armor, though his behavior remains unpredictable and occasionally abusive.

Yang is the chauffeur for Jim's family in the International Settlement. He drives through the increasingly dangerous checkpoints manned by Japanese soldiers to transport his wealthy employers.

Dr. Lockwood is a member of the affluent expatriate community in Shanghai. His lavish parties, featuring Chinese acrobats and conjurers, highlight the vast disparity between the European elite and the local population on the eve of the war.

Mr. Radik is an internee who attempts to keep intellectual curiosity alive among the prisoners. His lectures cover a variety of engaging topics, providing a brief mental escape from their grueling physical conditions.

Lieutenant Price is an aggressive British man who struggles with the psychological toll of the Japanese occupation. Having seemingly endured harsh treatment, he harbors deep resentment and actively looks for opportunities to express his anger.

Mr. Tulloch is a British internee focused on securing resources in the chaotic environment of the occupied territory. He is pragmatic and determined, often taking risks to scavenge supplies for his fellow survivors.

Captain Soong is a former officer in the Chinese puppet army who has turned to banditry. He commands a ruthless group of scavengers, exploiting the lawless vacuum of the Chinese countryside to loot and pillage.