Transparent Stained-Glass Windows (Russian: «Прозрачные витражи», romanized: Prozrachnyye vitrazhi) is the third novel in the Labyrinth trilogy of cyberpunk novels written by Russian science fiction writer Sergey Lukyanenko. Originally published online, the story features two endings, both of which are included when it was printed in the Atomic Dream anthology. Unlike the first two novels, Transparent Stained-Glass Windows is told from the point of view of a young female MVD operative who is sent to an isolated area of Deeptown, a virtual city created by Microsoft and IBM, to inspect the first virtual prison and locate any possible breakouts into Deeptown. She soon finds out that the prison is used by the Russian government to secretly conduct experiments on inmates. Throughout the story, she keeps referring to a jigsaw puzzle she began to complete during her childhood but never finished (one piece was missing). Source: Wikipedia (en)