Guest Stars Pearl Mackie as Alysse Tim Delap as Byron Kenichiro Thomson as Martin Adam Silver as Howard Celia Imrie as Margaret "Meg" Roylin Jess Chanliau as Ronnie Buckhurst Nana Mensah as Billie Appiah Georgie Henley as Pensy Penny Downie as Frances Munning Bhav Joshi as Anu Kapoor Michael McKean as President William Rayburn Miguel Sandoval as Miguel Ganon Graham Miller as Neil Barrow Sandy Amon-Schwartz as Sandy Richard Dillane as Tom Libby David Bark-Jones as Alistair Kemper-Waithe Joey Eden as Dan Pandora Colin as Lydia Trowbridge John Schwab as Roger Post Maggie Daniels as Louisa Alan Mahon as Warren Nancy Carroll as Philippa Pemberton James Payton as Brayer Carol Walton as Nurse Paul Tylak as Malakov Mo Sesay as Speyer George Potts as Lon Hammond Kehinde Cardoso as Paramedic Allen Watts as Ryan Jammy Kasongo as Troy Brewer Eric Underwood as Bobby Modello Stephanie Mae as British Embassy Staffer Martina Avogadri as French Reporter Nina Bowers as Paramedic Waseem Mirza as English Reporter Victoria Blunt as Paramedic Paula Kay as Nurse Belle Mattia Sonnino as Nurse Marco Sue Appleby as Anesthetist Miriam Lucia as Mills Shelley Draper as Nurse Sarah Ian Hughes as Dr. Kesten Akbar Kurtha as Ambassador Desai
