Natasha Romanoff, also known as Black Widow, confronts the darker parts of her ledger when a dangerous conspiracy with ties to her past arises. Pursued by a force that will stop at nothing to bring her down, Natasha must deal with her history as a spy and the broken relationships left in her wake long before she became an Avenger.

In 1942, an intelligence officer in North Africa encounters a female French Resistance fighter on a deadly mission behind enemy lines. When they reunite in London, their relationship is tested by the pressures of war.