The film is an adaptation of Frances Frederica Montrésor’s 1901 novel, 'The Alien: A Story of Middle Age,' described as a gothic mystery set in the Scottish Highlands. The cast includes Patsy Ferran, Josh O’Connor, Damian Lewis, and Lesley Manville, with Joel Coen reuniting with long-time collaborators Bruno Delbonnel (cinematographer) and Carter Burwell (composer).