In 1957, Countess Teresa Lubienska, a Polish resistance veteran who survived Auschwitz, is stabbed to death on a London Underground platform in front of witnesses who see almost nothing. Scotland Yard opens a case that goes nowhere, and this film works through the surviving files to lay out why. Historians and investigators weigh the two competing theories that have circulated for decades: a random attack by a petty criminal riding the Tube that night, or a targeted killing connected to Lubienska's wartime past among Polish resistance networks and postwar émigré politics in London. Archive photographs, contemporary press cuttings, and the original police documents are used to walk through the timeline of her final journey, the physical evidence collected at the scene, and the suspects who were investigated and released. The film does not resolve the case, since it remains officially unsolved, but it sets out clearly what the police knew, what they missed, and why a woman who survived a concentration camp died on a train platform a few miles from her home.