 | Finn Cole als Don Wallace |
 | Asa Butterfield als Willoughby Blake |
 | Hermione Corfield als Clemsie Lawrence |
 | Simon Pegg als Meredith Houseman |
 | Michael Sheen als The Bat |
 | Nick Frost als Woody Chapman |
 | Tom Rhys Harries als Clegg |
 | Isabella Laughland als Kay |
 | Kit Connor als Wootton |
 | Jamie Blackley als Caspar de Brunose |
 | Margot Robbie als Audrey |
 | Jo Hartley als Babs Wallace |
 | Jane Stanness als Matron |
 | Louis Strong als Smudger |
 | Jassa Ahluwalia als Yuri |
| Cory Chambers als Bello |
| Alan Drake als Butler |
| Charles Evans als Mikey |
| Charlie Fitzherbert als Tomkinson |
 | Alhaji Fofana als Chibwe |
 | Hanako Footman als Poppet |
| Gary Golding als Hedger |
| Rohan Gotobed als Scholar Bartlett |
 | Nick Kellington als The Beast |
 | Alex MacQueen als Lambert |
| Levi Masoet als Dr. François |
| Neil Pendleton als Red Dreads |
 | Max Raphael als Hargreaves |
| James Woodroffe als Teddy Chapman |
| Joshua Squire als Olympus Boy (uncredited) |
| Toby Cordes als Sparta Boy (uncredited) |
| Ted Day als Sparta Boy (uncredited) |
| Thomas Farrow-Tomson als Sparta Boy (uncredited) |
| Harry Isherwood als Sparta Boy (uncredited) |
| Aron Jackson als Sparta Boy (uncredited) |
| Mateusz Kobylec als Sparta Boy (uncredited) |
| Sam Redland als Sparta Boy (uncredited) |
| Zaak Conway als Tiny New Boy (uncredited) |
| Jack Webb als Xenephon Boy (uncredited) |
| Ben Wheeler als Xenephon Boy (uncredited) |
 | Lee Charles als Special Security (uncredited) |
| Nick Frost | Executive Producer |
| Simon Pegg | Executive Producer |
| Crispian Mills | Director |
| Charlotte Walls | Producer |
| Josephine Rose | Executive Producer |
| Dillon Bennett | Sound Designer |
| Matthew Button | Production Design |
| Peter Christelis | Editor |
| Tim Dennison | Line Producer |
| Abby Bowers | Graphic Designer |
| Christopher Raphael | Still Photographer |
| John de Borman | Director of Photography |
| Henry Fitzherbert | Story |
| Crispian Mills | Screenplay |
| Jon Ekstrand | Original Music Composer |
| Diego Suárez Chialvo | Executive Producer |
| Daniela Faggio | Art Direction |
| Simon Farmer | Sound Mixer |
| Doug Cooper | Sound Re-Recording Mixer |
| Emma Biggins | Production Manager |
| Colin Jones | Casting Director |
| Nick Wall | Still Photographer |
| Dillon Bennett | Supervising Sound Editor |
| Colleen Kelsall | Costume Designer |
| Crispian Mills | Story |
| Victoria Boydell | Editor |
| Dan Peacock | Unit Manager |
| Sebastian Barker | Visual Effects Supervisor |
| Clare Keyte | Set Decoration |
| Abby Bowers | Art Direction |
| Luke Passmore | Story |
| David Freeman | Editor |
| Henry Fitzherbert | Screenplay |
| Huberta von Liel | Co-Producer |
| Alex Watherston | Costume Supervisor |
| Peter Pedrero | Stunt Coordinator |
| Freddie Mason | Stunt Double |
| Anna Stephenson | Stunt Double |
| Neil Chapelhow | Stunt Double |
| Katy Bullock | Stunt Double |
| John Sharpe | Stunt Double |
| Laura Swift | Stunt Double |
| Ryan Oliva | Stunts |
| Gary Hoptrough | Stunts |
| Jake Osborn | Stunts |
| Gordon Alexander | Stunts |
| Russell MacLeod | Stunts |
| Chey Anich | Stunts |
| Jamie Stanley | Stunts |
| Pablo Casillas | Stunts |
| Ciara Elwis | Music Supervisor |
| Matt Biffa | Sound Supervisor |
| Jane Walker | Makeup Designer |
| Jane Walker | Hair Designer |
| Aurelia Thomas | Location Manager |
| Kieron Phipps | First Assistant Director |
| Francesca Brooks | Script Supervisor |
| Daniel Watkins | Production Coordinator |
| Uxue Iñurritegi | Production Secretary |
| Sacha Garrett | Production Assistant |
| Qasim Baig | Production Runner |
| Thomas Bassett | Second Assistant Director |
| Stephen Gallacher | Third Assistant Director |
| Emily Prieditis | Floor Runner |
| Sinead Leahy | Floor Runner |
| Sarah Teboul | Production Accountant |
| Toby Spigel | Casting Associate |
| Sam Barnes | First Assistant "A" Camera |
| Andrew Nowley | Second Assistant "A" Camera |
| Malcolm McLean | Camera Operator |
| James Leckey | First Assistant "B" Camera |
| Daniel Alexander | Second Assistant "B" Camera |
| Marina Selega | Camera Trainee |
| Torquil Fleming-Boyd | Steadicam Operator |
| James Markwick | Drone Operator |
| Greg Murray | Key Grip |
| Jody Knight | Grip |
| Charley Cox | Gaffer |
| Mark Keane | Best Boy Electric |
| Matt Risebrow | Assistant Location Manager |
| Rod Whiting | Property Master |
| George Mizen | Art Department Coordinator |
| Luke Gledsdale | Prop Maker |
| Sam Wendleken | Prop Maker |
| Nicola Matthews | Makeup Supervisor |
| Kay Bilk | Makeup Artist |
| Marianna Kyriacou | Makeup Artist |
| Steven Painter | Makeup Effects |
| April Church | Assistant Costume Designer |
| Deborah Tallentire | Tailor |
| Claire Louise Hardie | Tailor |
| Rosie Coppola | Tailor |
| Ben Rai-Green | Construction Manager |
| Natalie Laws | Scenic Artist |
| Scott McIntyre | Special Effects Supervisor |
| Rob Mayor | Creature Design |
| Noel Francis | Armorer |
| Alex Francis | Armorer |
| Stephen Forrest-Smith | Storyboard Artist |
| Tony Hatton | Unit Medic |
| Verity Wislocki | Post Production Supervisor |
| Conor Mackey | First Assistant Editor |
| Philip Scaife | First Assistant Editor |
| Rob Redford | First Assistant Editor |
| Rab Wilson | Visual Effects Editor |
| Matt Waites | Sound Effects Editor |
| Grace Averbuch | Sound Effects Editor |
| Rob Killick | Dialogue Editor |
| Michael Maroussas | ADR Editor |
| Emmet O'Donnell | Assistant Sound Editor |
| Hanse Warns | Foley Mixer |
| Christoph Oertel | Foley Mixer |
| Grace Averbuch | Foley Editor |
| Carsten Richter | Foley Artist |
| Stuart Morton | Music Editor |
| Adam Inglis | Digital Colorist |
| Alex Beyer | Digital Intermediate Producer |
| Christian Bull | Creature Design |
