In December 1981, a British psychiatry professor travels to Warsaw to deliver a university lecture, only to find herself trapped when Poland's government abruptly declares martial law overnight. After witnessing the secret police murder a young student, she becomes a target herself, forced to navigate a suddenly hostile, militarised city with the help of a politically active student host as she fights to survive and escape. A gripping, richly atmospheric Cold War thriller anchored by a tightly wound Lesley Manville performance, its tense cat-and-mouse plotting occasionally slowed by momentum that sags in the middle stretch.