Adrian Tofei's ambitious goal for We Put the World to Sleep was to combine the metaphysics of 2001: A Space Odyssey (1968) with the realism of The Blair Witch Project (1999), two of the movies that impressed and influenced him the most as a filmmaker.
The movie was shot over a period of 5 years in 13 cities, villages and remote locations across Romania, Turkey and Ukraine, using a diverse international cast. It's by far the most ambitious, difficult and disturbing project Adrian Tofei and Duru Yücel ever did, facing numerous challenges over the years and taking a toll on their personal lives as well due to the extensive periods of living in character (ironically, the movie deals with similar themes).
During the 7 years of production, Adrian Tofei and Duru Yücel lived partially in character and held world views slightly similar to those of their characters.
The script mostly consisted of plot points. After creating and maintaining an alternative psychological reality for their characters, Adrian Tofei and Duru Yücel shot about 150 hours of footage improvising guerrilla style, then came up with the details of the story in post-production while editing.
The most frustrating moments during production happened when the improvisation either went in a direction where Adrian Tofei and Duru Yücel no longer felt the need to record while in character, or went in directions which weren't doable due to budget limitations. Those directions were truthful to the story and character development, yet impossible to apply in practice, therefore Adrian and Duru had to break character for weeks or even months, put the entire production on hold and find new directions to move forward.