The game is in Russian and no other languages are supported. English localization was planned and a demo in Russian with English subtitles was released under the title Viy: The Story Retold, but those plans were eventually scrapped.
The game is not linear, so it's possible to get a different ending than the one from the story the game was based on. However, certain actions can lead to the death of some characters that didn't die in Gogol's story. Most of the cast are Ukrainian actors from Kharkov theater. The game's development team researched the era and the locations the story was set in to make the game look as authentic as possible.