In the film and trailer, when the new Kingsman recruits have their first nights sleep interrupted by a deluge of water pouring into the dorm, on-set, the scene went horrifically wrong. As writer, producer, and director Matthew Vaughn recalls "I shouted 'action!', the computer got it wrong and vrrrrssshh, everyone was twenty feet down underwater. Cameras, sound guys. People were in waders full of water, panic, everyone diving in, and pulling people out." The set, painstakingly planned and rehearsed using height markers and computer-programmed water tanks, washed away in a nearly Biblical flood when said computers went rogue. "Those actors weren't acting, they were absolutely terrified", shudders Vaughn. "It was awful for the first day of filming."
Colin Firth did 80% of his own stunts, according to stunt coordinator and second unit director Bradley James Allan.
Colin Firth worked out for around six months to be in top fighting shape and physical form in order to portray gentleman spy Galahad a.k.a. Harry Hart.
All of the action is framed centrally. The viewer's eyes never need to leave the centre of the frame.
During, and in the lead-up to, World Wars I and II, the British Intelligence Services often used tailor shops as fronts for their activities.
Nick English: The co-founder of Bremont Watch Company, who produced some this movie's fine British luxury brands as seen in the movie, as one of the Kingsman Gentleman Agents.