Trivia

According to co-writer Sabrina B. Karine, the average age on set was 28 years old.

The movie's working title was first "The No-One Boy", then simply "Simon".

Julie-Anne Roth was already supposed to play the mother of a young child who disappears in the woods and comes back with supernatural powers in Le portail (2010), but had to bow out before shooting began.

Both Léo and Martin Karmann are the sons of Sam Karmann, a French actor and director.

Martin Karmann he's Leo Karmann 's brother. According to the making of interview, Martin didnt want to audition as he thought people would think he got the job because of this. But Léo insisted and Martin was unanimously choses for the part.