Last year, 12,000 people gathered on the bank of the Thames to see Deadmau5 play in front of Millbank Tower, which was temporarily turned into a 390-foot projection screen. This year, Deadmau5 and Nokia went large...much larger. I went behind-the-scenes to see how they did it.

Following the Millbank Tower lightshow, Nokia called in Deadmau5 again for something equally unexpected but much more exclusive. The bright idea: light up a whole neighbourhood. "We wanted people to walk in and think, this is just a standard street, and then slowly everything starts to come to life," Adam Johnson from Nokia told us about the thinking behind the stunt.

It took three weeks to rig up the east end of Union Street in Southwark with robotic spotlights, LEDs, projectors and striplights. But this was no ordinary light show. Technically speaking, nothing like it had ever been done before. While your average Metallica concert involves something like 500 individual lighting cues, this used 200,000 for a 30-minute set. ML Studio took separate MIDI (musical instrument digital interface) notes and mapped them through a 3D visualiser onto as many outdoor surfaces and props as possible.

"Animating a light show in a sound package is kind of insane, but it made total sense to us. The computers are fast enough to keep up with it, so why not? We could play the whole street live through a MIDI keyboard if we wanted to," said Mark Louge from ML Studio. And it's not as if the street was simply turned into a massive equaliser, oh no. Each note was individually placed by the animators, so it was a matter of interpreting how the set should be visualised in 3D space.

"The collaboration with Deadmau5 has been amazing. Last year he was surprised at the scale of what we did, so he knew we could create something epic. This time he said, 'I'm up for it, I just want to play for longer'," added Adam Johnson. Mr mau5 disappeared and reappeared in a different location during the set, but at one point he was perched on a rooftop with the Shard looming over him in the background. Chances are you didn't see it for yourself, but you can watch the video here now.

So why didn't you hear about it? Because only the production crew and the 500 people on the guest list (mostly competition winners) knew when and where it was happening. More to the point though, how did Nokia manage to use Union Street as a brand platform without the local residents letting the cat out of the bag? Well, the free Lumia handsets probably helped, but with so many people in the know, it was a case of running a very tight ship. Everyone from the council and the police, to local shop-owners had to be on board, given virtually everything was lit up. Even the bins.

"Doing something original with software was the relatively easy part; trying to take over a street in London, that’s tricky! The jump from the studio to the street was huge," said Marcus Lyall, Creative Director at ML Studio.

So what was in it for Nokia? Apart from raising brand awareness of its Lumia range, and associating itself with cool stunts and music, it also had the perfect platform to show off its low-light camera capabilities of the Lumia 920 and 820 to the lucky few who attended. Aha...