London, 1941. Amongst the air-raid sirens and horrors of bombings, artist Harriet Yorke manages Calla House: a small community of people from different backgrounds - but good friends who pull together in times of crisis.
Like most Londoners contending with the Blitz, Harriet has grown used to withstanding danger, but when she goes on a late-evening stroll with her Cairn Terrier, George, and finds herself face-to-face with a killer, she unleashes a series of events that will put more than just her own life on the line . . .
London, 2019. Libby lives amongst her grandmother's paintings in Calla House - works of art into which Harriet poured all the horror of her wartime experiences, culminating in that one terrifying night.