This episode dives into the audacious life of Christina Skarbek, who operated as Christine Granville and became Britain's first female special agent of the Second World War, as well as its longest serving. We open with a 1944 prison rescue in Digne, France, where she walked through the front door of a Gestapo stronghold armed with nothing but cash and an enormous psychological bluff.

Tracing her path from aristocratic, financially unstable origins in Warsaw to daring infiltrations across the frozen Tatra Mountains, the story examines how a woman built for chaos repeatedly outmaneuvered the Gestapo. Her triumphs, including a megaphone-led mutiny of a 150-man garrison, stand against the cold institutional betrayal she suffered in Cairo and the bleak, stateless peacetime that ultimately led to her murder in 1952.

• The grocery-bag and ...