Utterly fascinating account of reverse engineering Netflix's recommendation system. The rabbit hole goes deeper than I had even dreamed, and Perry Mason is at the bottom of it.

So, after I'd secured my data, I called up Netflix's PR liaison, a Dutch guy named Joris Evers who keeps a miniature windmill on his desk. I told him we had to talk.

After I filled him in on what we'd done, I waited to hear his reaction, wondering if I was about to have my Netflix account permanently canceled. Instead, he said, "And now you want to come in and talk to Todd Yellin, I guess?"

Yellin is Netflix's VP of Product and the man responsible for the creation of Netflix's system. Tagging all the movies was his idea. How to tag them began with a 24-page document he wrote himself. He tagged the early movies and guided the creation of all the systems.

Yes, of course I wanted to meet Yellin. He had become my Wizard of Oz, the man who made the machine, the human whose intelligence and sensibility I'd been tracking through the data.

At our interview, Yellin turned to me and said, "I've been waiting for someone to bubble up like this for years."