1944. Newly recruited SOE agent Elisabeth Shepherd is faced with an impossible mission: to parachute behind enemy lines into Nazi-occupied France and monitor the new long-range missiles the Germans are working on. Her only advice? Trust absolutely no one. With danger lurking at every turn, one wrong move for Elisabeth could spell instant death. 2018. Betty is about to celebrate her 100th birthday. With her carer Tali at her side, she receives an invite from the Century Society to reminisce on the past. Remembering a life shrouded in secrecy and danger, Betty remains tight-lipped. But when Tali finds a box filled with maps, letters and a gun hidden in Betty’s cellar, it becomes clear that Betty’s secrets are about to be uncovered.