They are known for their work in the horror genre, and list their influences as Dario Argento, Roman Polanski, Clive Barker and John Carpenter.

[2][3] Julien Maury graduated from l’École Supérieure de Réalisation Audiovisuelle.

He worked for French television before directing documentaries, music videos and short films.

[citation needed] After the success of Inside, Maury and Bustillo were attached to at separate times to Halloween II, the sequel to Rob Zombie's remake of John Carpenter's Halloween as well as the remake for Clive Barker's Hellraiser.

The film was initially intended to be Bustillo and Maury's English-language debut and shot in the United Kingdom but they moved to a lower-budget French production after they found that they were losing creative control over their story.