The movie is based on true events but the author decided to protect the privacy by completely changing the places, dates and the characters' names. She used a pen name for herself as well: Jessica was named her dog and Koch was her maiden name.
This movie is a film adaptation of the book So Near the Horizon (Dem Horizont so nah) by Jessica Koch, first published in 2016.
Jessica Koch (the author of the book the movie was based on) appeared in the movie as a spectator in the audience of the kickbox competition.