It started last week with a call to action from China's leader, Xi Jinping. Too many of the country's children need glasses, he said, and the government was going to do something about it.
It ended Friday with billions of dollars being wiped from the market value of the world's largest video game company.
New controls on online games were among Chinese authorities' recommendations for reducing adolescent nearsightedness on Thursday, sending shares in the country's leading game publisher, Tencent, tumbling the next day. Shares of Japanese game makers like Capcom, Konami and Bandai Namco also fell Friday, a sign of the size and importance of the Chinese market.
The sell-off is the latest in a series of government-related stumbles for Tencent, one of the world's largest technology companies. Chinese state media has blamed video games for causing young people to become addicted, lowering their grades and worse. An incident last year, in which a 17-year-old in the southern city of Guangzhou died after playing a smartphone game for 40 hours straight, received wide attention.
As the biggest game distributor in the world's biggest game market, Tencent has grown fantastically rich in recent years. It has bought up game developers around the world, including the makers of influential titles such as "League of Legends" and "Clash of Clans." It owns a stake in Epic Games, creator of the international blockbuster "Fortnite."
Back at home, Tencent also operates China's most popular messaging app, WeChat, and processes a big chunk of the smartphone payments that are now used to make transactions of all kinds in the country.
But over the past year, Tencent's hugely profitable game business has come under fire as Beijing takes a more forceful approach to guiding Chinese culture — a reminder of the state's growing role in deciding the fortunes of the country's largest and most innovative private companies.
Last year, the Communist Party's official mouthpiece, the People's Daily, called the Tencent-developed battle game "Honor of Kings" a "poison" on young minds. In response, the company imposed limits on the amount of time young people could spend playing it each day.
More recently, Chinese regulators blocked sales of another Tencent title — "Monster Hunter: World" — because it was deemed too gory. The company's stock also took a slide after executives said that a bureaucratic reshuffle had slowed the process for getting licences to make money on new games such as the mobile version of "PlayerUnknown's Battlegrounds."
Tencent's shares fell 5 per cent in Friday trading in Hong Kong. A company spokesman declined to comment.