Cast List – Urban Nightmare: London Calling
| Cabinet | |
| Prime Minister | Robin Sealey |
| Secretary of State for Health and Social Care | – |
| Secretary of State for the Home Department | Alex Beck |
| Secretary of State for Defence | Mayank Jha |
| Opposition Party | |
| Leader of the Opposition | James MacFarlane |
| Shadow Defence Secretary | – |
| Shadow Home Secretary | – |
| LOCC (London Outbreak Crisis Committee) | |
| Commissioner of the Metropolitan Police | Mili Gupta |
| Vice Chief of Defence Staff | Alex Vince |
| Government Chief Scientific Advisor | William Barton |
| CEO of London NHS | Matt Bambridge |
| London Fire Commissioner | John Attwell |
| Intelligence | |
| Head of MI5 | Harrison Tatem-Wyatt |
| Special Agent | – |
| UK Military | |
| Commander Operation Wellington | Tommie Rohs |
| 20 Armoured Infantry Brigade | Robert Kemp |
| 16 Air Assault Brigade | Linas Kondrackis |
| NATO Military | |
| Commander of USA Contingent | Anthony Howgego |
| Commander of Canadian Contingent | Joseph H |
| Commander of Dutch Contingent | Richard Stephenson |
| Metropolitan Police | |
| Met Police Gold Commander | Esme Moore |
| Gold Command Operational Staff | – |
| Silver Command West | Declan |
| Command West Staff | Diggory |
| Silver Command East | Graham van Rensburg |
| Command East Staff | Jonathan Fyfe |
| NHS London Foundation Trust | |
| London Ambulance Service | Darrell Ottery |
| NHS Hospital Trauma Teams | Rachel Turner |
| NHS Epidemiology Research Team | Stephen Silverstone |
| Press | |
| BBC News Editor in Chief | Russel Kent |
| BBC News Political Editor | Barbara Croker |
| Greater London Authority | |
| Mayor of London | Jerry Elsmore |
| Head of Mayor’s Crisis Team | Oliver Moody |
| Head of Mayor’s Office for Policing and Crime | Tirion Rees Davies |
| London Fire Brigade | |
| Head of London Fire & Emergency Planning | Sebastian Reid |
| Fire & Rescue Operational Coordinator | Ben Ford |
| Control | |
| Game Control | Jim Wallman |
| Military Control | Matilde Robinson |
| Political/Intelligence Control | Ollie Sliney-Biss |
| LOCC Control | John Mizon |
| Map/Player Control | John Keyworth |
| Map/Player Control | Ed Silverstone |
| Medical/Science Control | Chrissy Sliney-Biss |