Hellboy comes to England, where he must defeat Nimue, Merlin's consort and the Blood Queen. But their battle will bring about the end of the world, a fate he desperately tries to turn away.
| Hellboy / Anung Un Rama | David Harbour |
| Vivienne Nimue, the Blood Queen | Milla Jovovich |
| Trevor "Broom" Bruttenholm | Ian McShane |
| Alice Monaghan | Sasha Lane |
| Ben Daimio | Daniel Dae Kim |
| Lobster Johnson | Thomas Haden Church |
| Gruagach (voice) | Stephen Graham |
| Gruagach | Douglas Tait |
| Lady Hatton | Sophie Okonedo |
| Lord Adam Glaren | Alistair Petrie |
| Merlin | Brian Gleeson |
| Ganeida | Penelope Mitchell |
| Arthur | Mark Stanley |
| Baba Yaga (voice) | Emma Tate |
| Baba Yaga | Troy James |
| Esteban Ruiz / Camazotz | Mario de la Rosa |
| Alice's Mother | Ava Brennan |
| Alice's Father | Anthony Delaney |
| Agent Madison | Atanas Srebrev |
| Agent Strode | Dawn Sherrer |
| Grigori Rasputin | Markos Rounthwaite |
| Professor Doctor Karl Ruprecht Kroenen | Ilko Iliev |
| Von Krupt | Joel Harlow |
| Leopold Kurtz | Dimiter Banenkin |
| Ilsa Hepstein | Vanessa Eichholz |
| Sister #1 | Nadya Keranova |
| Sister #2 | Maria Tepavicharova |
| Sister #3 | Ana Tabakova |
| Priest | Terry Randal |
| Referee | Christopher Mata |
| Butler | Michael Heath |
| Dr. Edwin Carp | Rick Warden |
| August Swain | Nitin Ganatra |
| Leni Riefenstahl | Kristina Klebe |
| Sgt. Whitman | Charles Shannon |
| Sir Malcom Frost | Carl Hampe |
| Abbot | Tony van Silva |
| Novice | Josh Finan |
| Huntsman | Jonathan Steele |
| M-11 Operative | Simon Feek |
| Baby Alice | Jasmine Audoux-Prevot |
| Leprous Hag #1 | Meglena Karalambova |
| Leprous Hag #2 | Anna Bankina |
| Leprous Hag #3 | Rut Rafailova |
| Mrs. Harker | Laila Morse |
| Gunsmith | Peter Oxley |
| Monk | Nikolay Stanoev |
| Mother | Manal El-Feitury |
| Child in Parking Lot #1 | Elizabeth Mehari Kahsai |
| Child in Parking Lot #2 | Said Barry Abdulai |
| Sarah Bethany Hughes | Katya Peneva |
| Anchorwoman | Natasha Kaplinsky |
| Man #1 | Valentin Stojanov |
| Man #2 | Victor Rangelov |
| Man #3 | Vasil Tsvetkov |
| Man #4 | Joshua Samuel Hector |
