National Geographic's Photo of the Day—captured by Simon Kwan—shows Hong Kong in all its glorious urban madness. When I first saw it I thought it was a collage made with multiple shots and mirrored images. It's not. It's just the city photographed from Beacon Hill.
Six years ago, photographer Joey L. was accidentally caught on film by a fellow snapper. Six years later, the pair discovered they'd been within metres—and caught each other on camera. Here, we republish Joey L.'s account of what happened.