It is 1939, and working-class Evie Bishop has received a scholarship to study mathematics at Oxford when tragedy turns her life upside down. Evie must seek a new future for herself and, inspired to contribute to the war effort, joins the Women’s Auxiliary Air Force as an Ops Room plotter. Posted to a fighter station on the Sussex Coast, Evie befriends two other WAAFs. But the German bombers seem to know more than they should about the base’s operations, and soon Evie, May and Jess are caught up in a world more dangerous than they ever imagined.

Pearl has given up on her dreams of being a journalist after being denied a promotion because of her gender. Joining the WAAF as a radio telephone operator for Bomber Command, Pearl's new job at RAF Fenthorpe serves two purposes – providing an income for her grandmother, and keeping a close eye on her younger sister, Thea, an instrument repairer at another Lincolnshire bomber station.

Flying instructor Ellie Simpson has grown up a tomboy. She's never had an interest in the latest fashions or finding a husband; her only passion is flying her beloved Tiger Moth. But when war is declared, she is no longer be able to do what she loves most - fly.

London, 1940. Bombs fall and Josie Banks’ world crumbles around her. Her overbearing husband, Stan, is unreachable, called to service. Her home, a ruin of rubble and ash. Josie’s beloved tearoom boss has been killed, and Josie herself is injured, with nothing left and nowhere to go. Evacuated to the English countryside, Josie ends up at the estate of the aristocratic Miss Harcourt, a reluctant host to the survivors of the Blitz. Now a threat looms larger than anyone imagined. And a dangerous secret is about to upend Josie’s life again.

When duty calls, East End girl Minnie Wolton isn’t afraid to do her bit. She’s excited to be joining the ATS girls and although she knows life at the barracks will be tough, she’s not one to quit! She just hopes the other girls are all good sorts. With her husband away fighting, Eileen Ruffel is glad of the break from her unhappy marriage. She just wants to make a success of the ATS girls and maybe find happiness too. Along with the other girls, Minnie and Eileen strike up a firm friendship. The training is hard, but they are determined to prove they are the best new recruits.