In 1992 Russia, music teacher Nikolay Chizhov moves into a communal apartment in St. Petersburg, where he discovers a mysteriously boarded-up window in his new room.
The next day, Chizhov learns from a returning elderly resident that the window periodically opens to Paris for a few weeks every few decades.
Realizing the limited time to access Paris, Chizhov's neighbor, Gorokhov, and his family begin cross-border ventures through the window, from selling souvenirs to transporting a Citroën 2CV into Russia.
Meanwhile, one of Chizhov’s guests, a former Soviet official, manages to rack up a taxi fare, which he convinces the French Communist Party to cover.
Months later, Chizhov and Gorokhov spot the old resident’s cat emerging from a crack in the wall, sparking their hopes of reopening the path to Paris.