My first day in Shanghai did not go particularly well. I had just arrived, jumped into a Didi, got out at my destination, watched the car disappear into traffic, and reached into my pocket.

No phone.

There went my communication, payments, maps, entertainment, and approximately 87 percent of my ability to function as a modern human being. Not exactly the start to the trip I had in mind.

Luckily, there was one of those small neighborhood police stations that seemed to be everywhere in China’s big cities. So I figured, whatever, throw the Hail Mary. I walked in to see whether a city with millions of people and presumably more important things to deal with could help a hapless tourist who had essentially lost his wallet and could provide almost nothing useful about the driver. No name. No license plate. Just roughly where I got out.

But that’s why quarterbacks throw Hail Marys.

The super-friendly officer pulled out a translation app and asked where the Didi had dropped me off and around what time. I pointed out the location, and a few clicks later, there I was on a screen, reliving the previous ten minutes and watching myself get out of the car.

She found the vehicle on nearby camera footage, pulled the license plate, did some magic keystrokes I still don’t understand, figured out which driver it belonged to, and contacted him. Not long afterward, I had my phone back.

I remember walking out thinking two things. First, that was insanely efficient. Second, holy shit, they can do that?

And for one brief moment, against pretty much every instinct I have about state surveillance, I thought, Thank God for the surveillance state.

Because in that moment, surveillance was fantastic. I had lost something important, and a system capable of reconstructing where I had been, which car I had taken, and who had been driving it solved my problem remarkably quickly. If the surveillance state had asked me to leave a review, I probably would have given it five stars.

Of course, sarcasm aside, that exact same sequence looks very different if the person being located is a state target. Same cameras, same data, same efficiency, completely different purpose.

That tension is what I still find fascinating about surveillance technology, whether it’s Shanghai, London, or New York. There are real benefits to systems that can help find a missing child, solve a crime, manage traffic, or return an idiot tourist’s phone. Pretending those benefits don’t exist makes the conversation too easy.

But convenience and control can live surprisingly close to one another. A system that can find your lost phone can, by definition, find you too.

And here’s the part I still can’t quite get over. This happened in 2019.

Crazy to imagine what the technology can do now.

Roll credits.