Nisei Blue by Mieko Ouchi

John Finch, a retired homicide detective, returns to the Vancouver bar where one of his first cases began in the 1930s, but still remains unsolved. Haunted by the unknown, John is desperate to find answers with the help of his former partner and a bartender who has been around since the beginning of the case. But John’s early-onset Alzheimer’s proves to be the barrier between remembering and knowing. Nisei Blue is a politically charged mystery that delves into the bombing of Pearl Harbour and Japanese internment, while remaining present in the gripping mystery of an unsolved case.