Working hard to sidestep accusations of being merely a glorified TV programme, this movie spin-off from the long-running BBC show throws caution (not to mention key characters) to the wind. Likable Kit Harington is Will Holloway, returned from decommissioned exile after M15 loses top terrorist Qasim (Elyes Gabel) and furtive Harry Pearce (Peter Firth) goes off-grid. The plot is all sub-Tinker Tailor twisty turns, the action full of Bourne-lite shoot-outs and chases, with an emphasis on techy surveillance. It’s nonsense, but there’s fun to be had in the endless double-crosses, and fans of the TV show’s trademark gruff face-offs won’t feel disappointed. Snappy editing by Jamie Pearson keeps the tempo admirably brisk.