George Clooney as Augustine Lofthouse

Felicity Jones as Sully

David Oyelowo as Adewole

Caoilinn Springall as Iris

Kyle Chandler as Mitchell

Demián Bichir as Sanchez

Tiffany Boone as Maya

Sophie Rundle as Jean

Ethan Peck as Young Augustine

Tim Russ as Mason Mosley

Miriam Shor as Mitchell's Wife

Lilja Nótt Þórarinsdóttir as Frantic Woman - Katherine

Hanna María Karlsdóttir as Older Woman

Atli Óskar Fjalarsson as Soldier

Tia Bannon as Jasmine

Grant Crookes as Scientific Beneficiary (uncredited)