It was a cold, wet night, and we were asking 75 people to walk between Ladbroke Grove and Trellick Tower, watching video graffiti as they went. And to make it trickier, there were stories for them to hear, stops for them to make, and a deadline: we all had to reach the end before the video graffitists' portable batteries ran out. A little astonishingly, the 75 people complied; we walked, stopped, talked, discovered, and got to the end with thirty seconds to spare.

The walk was organised by Up Projects as part of Kensington and Chelsea's Across the Street, Around the World season; the video graffiti came from Moth, who have fantastic wearable projector units that let them cart around projected video on a whim. (Well, on a whim and a backstrain: the system weighs close to fifteen kilograms). My job was to work on a playful event structure to fit around the fundamental experience of "follow some lights around the Westbourne Park area", and then to facilitate the event itself.

An abstract pattern projected onto a brick wall.
One of Moth's more abstract projections

It was important for the focus of the walk to be on following the projected videos. We decided the best way to make sure the event structure supported this, rather than detracted from it, was to arrange the whole walk around light. People would follow Moth's light trails, and they'd also look out for the 250 glow-bracelets hidden along the path. Anyone who found a bracelet was encouraged to pick it up, with rewards for the people who found the most, and we hoped that the competitive element might help to keep the audience moving along quickly. It seemed to work, especially in the case of the nine or ten children who'd come along.

Holly helps a small child to read from a card to the assembled crowd.
One of the players reads out a story.

Shaun and Ed from Moth had spoken to people who lived around the area, and gathered five true stories linked to locations along the route: the market, the skate park, the Muslim Cultural Heritage Centre, Golborne Bridge, and Trellick Tower. We stopped in each of these locations while Moth played video tailored to the story. The video was quite abstract, and we needed a way to get across the story more explicitly — so keeping up the treasure-hunt structure, we hid the stories in several pieces around the locations, looped around with more glow rings. Players who found the pieces of the story would read them out to the rest of the group (or to give them to me to read out, if they were shy...).

The walk finished at a private room in the Number 10 bar, and to keep the light theme we'd arranged for a photographer to take long-exposure pictures of light patterns drawn by the audience members, using torches and the glow bracelets they'd collected. Some drew pictures, some scribbled, one made several attempts to write a letter to his mum, a couple even reviewed the walk (one wrote "cold"; the other, "wow"). Anyone who'd found at least six glow-bracelets received a glossy print of their picture in the post.

Long-exposure photograph showing an indeterminate figure in front of a wall, writing 'wow' with a torch.
A player's quick review of the walk.