Fionn Whitehead Tommy Tom Hardy Farrier Mark Rylance Mr. Dawson Kenneth Branagh Commander Bolton Cillian Murphy Shivering Soldier Barry Keoghan George Harry Styles Alex Aneurin Barnard Gibson Damien Bonnard French Soldier Lee Armstrong Grenadier James Bloor Irate Soldier Tom Glynn-Carney Peter Jack Lowden Collins Luke Thompson Warrant Officer Michel Biel French Soldier 2 Billy Howle Petty Officer Mikey Collins Soldier Callum Blake Stretcher Bearer Dean Ridge Soldier at the Gap Bobby Lockwood Able Seaman Will Attenborough Second Lieutenant Adam Long Sub-Lieutenant Kevin Guthrie Highlander 3 Calam Lynch Deal Sailor Bill Milner Lone Private Harry Collett Boy Michael Caine Voice on Radio Johnny Otto Captain Marshall (uncredited)