Helen Mirren and Aaron Paul have joined the cast of drone warfare thriller “Eye in the Sky.”

Colin Firth also stars in the film produced by eOne and Ged Doherty’s Raindog Films.

As previously announced, Firth and Doherty will produce the film alongside Xavier Marchand, who will oversee production for eOne, in close collaboration with eOne’s senior VP of filmed entertainment Benedict Carver. Gavin Hood directs from a Guy Hibbert screenplay.

EOne Films Intl. is handling sales in Cannes for the U.S. and all territories outside of the U.K., Canada, Benelux, Spain, and Australia/New Zealand, where eOne will directly distribute the film.

Production is expected to begin in South Africa in September.