Brandywine Productions was interested in a follow-up to Omega as soon as its 2015 release, but the new management at Warner Bros. postponed those plans until 2016. That year Brandywine picked Cuarón to write after reading his script for Hellboy 3 and Pacific Rim 2, and once that film became a hit in 2015, Warner greenlit Omegas, that would also be directed by Cuarón, with a budget of approximately $18 million. The script was written with a war film tone strongly influenced by the Iraq War and World War II to contrast the horror motifs of the original Omega. It was filmed in England at Pinewood Studios and at a decommissioned power plant in Acton, London.