Identical twins Maggie and Tillie are thriving in 1940s London. Waitresses in one of the city's finest institutions and both with budding romances, the war could not feel farther away.

But, slowly, the tides begin to change. The war in Europe is creeping toward the UK, and the men are being called to aid in military efforts. Tillie's fiancé Colin joins the RAF, flying dangerous missions over Germany, and Maggie's childhood love Micah finds himself far away in France, with no way to return. Devastated but determined, the twins resolve to do their part for their country - Maggie in the Women's Voluntary Service and Tillie for the British Red Cross.

Then, the Blitz begins. And everything changes.

Nightly airstrikes wreak havoc on the city, leaving ruin in their wake. Ambulance shifts for Tillie become desperate missions to pull injured women and children from the rubble, while the constant fear for the fates of their beloveds, far from home, is almost too much for the girls to bear.

And when tragedy strikes for both sisters, they know nothing will ever be the same again.

Will the twins be strong enough to protect themselves and the ones they love? And can true love really prevail when the skies are darkened by war?