Major Henry Scobie serves as a police officer in a British West African colony during the Second World War, a devout Catholic torn between duty and love.

Stationed in a coastal colonial outpost in wartime West Africa, 1940s, Scobie prides himself on his incorruptibility. Yet as merchant ships crowd the harbour and the war tightens its grip on the empire, his private life begins to unravel. His wife Louise longs to escape the heat and isolation of the colony, and Scobie, desperate to ease her suffering, borrows money from a corrupt trader - a compromise that entangles him in blackmail.

When he falls in love with Helen Rolt, a young widow shattered by loss at sea, Scobie finds himself divided between compassion and betrayal. Each lie told to protect one-woman wounds another; each attempt at mercy becomes a sin against his faith. His Catholic conscience offers no comfort, only a harsher reckoning.

Set against the uneasy hierarchies and racial tensions of a British West African colony during the Second World War, The Heart of the Matter is mid-twentieth-century historical fiction driven by moral conflict.