Guest Stars Cush Jumbo as Lois Habiba Nicholas Farrell as Brian Green Katy Wix as Rhiannon Davies Lucy Cohu as Alice Carter Susan Brown as Bridget Spears Peter Capaldi as John Frobisher Luke Perry as David Davies Ian Gelder as Mr Dekker Julia Joyce as Holly Frobisher Bear McCausland as Steven Carter Madeleine Rakic-Platt as Lilly Frobisher Hilary MacLean as Anna Frobisher Rhodri Lewis as Johnny Davies Liz May Brice as Johnson Aimee Davies as Mica Davies Louise Minchin as Newsreader Simon Poland voices 456 Gregory Ferguson as Young Clem Paul Copley as Clemet McDonald Colin McFarlane as General Pierce Ben Loyd Holmes as Operative Charles Abomeli as Colonel Augustus Oduya Deborah Findlay as Denise Riley Lachele Carl as Trinity Wells Anthony Debaeck as French Newsreader Nicholas Briggs as Rick Yates Patrice Naiambana as Defence Secretary Sophie Hunter as Venessa