He hardly seems the guy to shake China’s scientific establishment. Geng Hongwei is a PhD dropout-turned-influencer. He posts technical videos for a general audience, leavened with cartoon memes. But in April his words, aimed at cancer researchers at a top Chinese university, triggered an earthquake. “I hope you’ll take academic fraud more seriously in the future,” he deadpanned, before demonstrating that the scientists had faked their data—and clumsily.