The story is loosely based on an existing phenomenon called skyquake, where a loud booming sound is reported to originate from the sky. Many, fake and purportedly real footage can be found on the web.
Filmed in 9 days.
In spite of having a screenplay, many dialogues were improvised. Director József Gallai encouraged the actors to do so.
The two principal actors shot more than an hour of the complete film.
Originally, the movie was planned to be filmed in 2016 and 2017 with a more traditional approach and a biblical story. In 2021, director József Gallai found his notes and ideas on his computer, though he wrote the script with a different concept and filming style instead.