The fly was a combination of puppet and a costume worn by the dog that also featured in the film.
Director Quentin Dupieux claimed that he pitched the movie as a mix between E.T. and Dumb and Dumber.
During an interview in the French magazine CinemaTeaser, Dupieux hinted that he was ready to make a sequel if the film exceeded 500,000 admissions in France. The sequel would be called Tentacles.
Adèle Exarchopoulos's character in Mandibules, Agnès, is a parody of Swedish climate change activist Greta Thunberg, who is autistic and was underage when the film was written and shot.
The film was released in France on May 19, 2021 by Memento Films. Its release was delayed several times from an original December 2020 date due to the COVID-19 pandemic.