When Rose Browns husband is killed at Dunkirk in 1940 she feels as though shes lost a part of herself. Rose cant imagine the future without Ray but shes certain he would have wanted her to start again. She decides to volunteer as a postwoman in West London & when she courageously rescues a young boy from a bombed-out house & takes him home she finds a new sense of purpose. Traumatised from losing his mother in the ruins seven-year-old Alfie is also rebellious & withdrawn. However he touches the hearts of Roses family & with kindness patience & love they eventually win his trust. But then a handsome stranger Johnny Beech turns up on the doorstep looking for his son & everything changes...