On the eve of China’s grand military parade, an activist in a city with 30 million people staged a protest that doubled as performance art, proof that defiance can still surface, and survive, even in one of the world’s most surveilled states.

At 10 p.m. on Friday in Chongqing, a large projection on a building lit up the night with slogans calling for the end of Communist Party rule. “Only without the Communist Party can there be a new China,” read one. Another declared: “No more lies, we want the truth. No more slavery, we want freedom.”

It took the police 50 minutes to locate where the projection was coming from — a hotel nearby — and shut it down. That’s usually the end of such protests in China. But not in this case. A few hours later, the activist released video footage of five police officers entering the hotel room, rushing to the window and finding the projector hidden behind a half-closed curtain. While four of them were fiddling to shut it down, another officer pointed with surprise to a surveillance camera aimed at them.

A handwritten letter addressed to the police was on the coffee table: “Even if you are a beneficiary of the system today, one day you will inevitably become a victim on this land,” said the letter, which the activist also circulated online. “So please treat the people with kindness.”

The next day, the man who staged the incident, Qi Hong, published another image from surveillance footage showing police officers questioning his frail, hunched mother in front of her village home.