no TopFlix. The Lost Letter (Russian: Пропа́вшая гра́мота, Propavshaya gramota), or A Disappeared Diploma, is a 1945 Soviet animated film directed by the Brumberg sisters and Lamis Bredis. It is the first Soviet cel-animated feature film. It was produced at the Soyuzmultfilm studio in Moscow and is based on the story with the same name by Nikolai Gogol.