Fragility and forgetfulness have left 82-year-old Iris vulnerable and in the care of her manservant, Mamdooh. Stiflingly quiet and claustrophobic, Iris's Cairo house is suddenly disturbed by the unexpected arrival of her troubled and willful granddaughter, Ruby, who, laboring under a fraught relationship with her family, has run away from England to seek solace with the grandmother she hasn't seen for many years. An unlikely bond arises as the two women open themselves up to one another and Ruby helps Iris document her deteriorating memories of the vibrant life she enjoyed in Cairo during World War II, a time when she lost her heart to her one true lovethe enigmatic Captain Xan Molyneuxand then lost him to the ravages of the war. It is the need to recover Iris's past and solidify Ruby's present that leads the two women into terrible danger in the Egyptian desert.