Mrs. Drover's house appears strange to her because the scene that greets her inside is incongruous with what she sees outside. Essentially, the German bombing campaigns have failed to destroy evidence of previous human activity in the house.
Yet, outside the house, there is destruction everywhere. Parapets and chimneys are broken, and architectural damage in buildings is evident. Meanwhile, an eerie stillness pervades the street where Mrs. Drover's house is located. The only evidence of life appears to be a stray cat, and Mrs. Drover does not see another human being on the streets.
Inside the house, evidence of previous human activity has been preserved. There is a yellow smoke stain above the white marble mantlepiece, a ring left by a vase atop a writing table, and a bruise in the wallpaper left by a china door handle.
Mrs. Drover sees traces of her old life everywhere, and she is besieged by her memories. However, no one can live in the house under the present circumstances. There is the feeling that life is fragile and can be rendered meaningless in the midst of war. So, Mrs. Drover's house appears strange to her because the ambiance inside the house is totally incongruent with what's outside. Essentially, destruction is juxtaposed against a previously normal existence: the two are mutually exclusive in nature.