| Name (Sort) | Character (Sort) | |
| •Kevin Zegers | played | Mark Muir (12Eps.) |
| •Alessandra Mastronardi | played | Sofia Silvestri (12Eps.) |
| •Derek Jacobi | played | Lord Pirrie (12Eps.) |
| •Neve Campbell | played | Joanna Yaegar (12Eps.) |
| •Ophelia Lovibond | played | Kitty Carlton (12Eps.) |
| •Billy Carter (2) | played | Thomas Andrews (12Eps.) |
| •Branwell Donaghey | played | Michael McCann (12Eps.) |
| •Martin McCann | played | Conor McCann (12Eps.) |
| •Ian McElhinney | played | Sir Henry Carlton (12Eps.) |
| •Valentina Corti | played | Violetta Silvestri (12Eps.) |
| •Denise Gough | played | Emily Hill (12Eps.) |
| •Edoardo Leo | played | Andrea Valle (12Eps.) |
| •Gray O'Brien | played | Bruce Ismay (12Eps.) |
| •Michael McElhatton | played | Albert Hatton (12Eps.) |
| •Liam Cunningham | played | Jim Larkin (12Eps.) |
| •Chris Noth | played | JP Morgan (12Eps.) |
| •Massimo Ghini | played | Pietro Silvestri (12Eps.) |