De página de trivia da IMDb para o filme:
The actors communicate in Ukranian sign language - anecdotally, users of western European sign languages may understand about 20% of it.
Director Miroslav Slaboshpitsky does not understand sign language and had to have interpreters on set to communicate and make sure that the actors were sticking to the script.
Quanto à falta de legendas, foi intencional. Diz o diretor do filme:
“I am very glad that my film will be released in the United States,” Slaboshpitsky said. “I have always believed in the universality of film’s language, and have always believed that dialogue and subtitles change the way different audiences perceive the film in different countries.”