The Elephant Never Forgets

"Anna often had the impression of being imprisoned within a maze, five minutes before closing-time. Its windings were neither numerous nor complicated; but, if she lost her head and took a wrong turning in her haste, she might reach the outlet-only to find the door locked."

The "maze" is Soviet Russia, where Ann Brown (alias "Anna Stephanovitch"), a young English woman, lives quite happily for one summer. But then friends of her are arrested. Fear begins to spread. Terror reigns the country. Will Anna reach the "outlet", before the "door is locked"?