Our experience of shooting the opening sequence was that it was, generally, a success. We had traveled to London with the slight expectations that something could go horribly wrong at any moment, such as having our equipment confiscated by authorities, however Trafalgar Square turned out to be an excellent filming location, with relative ease in pacing ourselves so we could capture all the shots we required and the only rush being the one against daylight (and even then we still had plenty of time). We were surprised at the lack of interest in our filming, while some passersby stared during some of our more outrageous stunts, such as Richard Young collapsing into the fountain and Lee Davidson sprinting the entire length of the square, none of the security guards approached us or any of our production team to query us about our (innocent) intentions. Our actors, for the most part, knew their lines and had mastered the performances within a number of takes, and both me and Nicholas found handling the filming equipment to be straightforward while also an interesting challenge in some parts as we had to run alongside our main actor without making the footage look unprofessional.
The only major concern we had during the day was the problem we faced regarding our planned fight sequence in the disabled elevator near the toilets in Trafalgar Square. As per the screenplay, and as visible in our storyboard animatic, our intention was to shoot a brief close quarters combat scene in the elevator, which meant we had to have access to it for filming purposes. However an irritating cleaner that waltzed into the area at every opportunity, as well as an elderly Oriental man who seemed to enjoy traversing up and down the elevator, meant we were unable to film what we had planned and had to relocate the sequence to an alternate location that would appropriate in the whole scheme of things as we did not wish to change the storyline. Thankfully, Nicholas came up with the idea of using the adjacent steps to shoot the fight. Though this mean a complete re-haul of the choreography, this was swiftly done, and whilst it did not have the cinematic flair of the elevator fight sequence, we found it worked just as well visually, as well as most importantly, practically.
Some minor problems that we did encounter, however, included slight rainfall which resulted in visible drops on some of our shots (which in the end did not make too much difference) and the obvious constant changing crowds, however the audience will not notice this due to the fast paced nature of the sequence. All in all, the shooting on the day was beyond satisfactory and after a brief haul through all the footage we know we have everything we need and thus will not require re-shoots of any kind.