Financial influencer Keith Gill, also known as Roaring Kitty, in 2019. His return to social media in 2024 has catalyzed another meme stock frenzy. Credit - Pavlo Gonchar—SOPA Images/LightRocket/Getty Images

A single JPEG has catalyzed yet another rabid surge in the stock price of the video game store GameStop: its price jumped by more than 70% on Monday morning.

On the evening of Sunday, May 12, a man named Keith Gill posted an illustration on X of a man bolting upright in his chair. Gill, who goes by handle Roaring Kitty, is something of a digital folk hero to many amateur investors—he was one of the major catalysts of the WallStreetBets craze of 2021. His reappearance and the subsequent enthusiasm—coupled with other rising “meme stocks”—suggest that the U.S. is fully in the midst of another period of meme stock frenzy, in which small-scale investors rally together to push the stock market in unpredictable ways. On Monday, GameStop’s shares briefly passed $36—its highest price since August 2022—and were halted multiple times for volatility. And GameStop topped both Google and X’s top trends list.

In late 2020, Gill became renowned for his stock market advice on YouTube and the subreddit Wall Street Bets. In particular, he advised his fellow investors to buy GameStop shares, believing that they were undervalued. Some major Wall Street institutions, conversely, were betting on GameStop to fail, as a declining number of people went to physical stores to buy video games, instead purchasing them online.

But a sprawling online community soon rallied around Gill’s thesis, hyping up GameStop with memes and other posts on social media. Millions of everyday people soon bought shares, pushing its price to unprecedented heights and punishing the hedge funds who had bet against it. GameStop soon became the textbook definition of a “meme stock,” or a stock whose value was driven more so by social media enthusiasm as opposed to any sort of underlying financial metrics. The GameStop saga showed Wall Street traditionalists that coordinated small-scale retail investors could have an outsize impact on the stock market.

Read More: Dumb Money and the Complicated Legacy of GameStop

Interest in meme stocks waned after a few months, and Gill mostly disappeared from public life. In September 2023, his story was canonized in the Hollywood film Dumb Money, in which he was played by Paul Dano. The film portrays Gill’s unwavering belief in his investments, and his refusal to sell shares even when they were worth millions of dollars—because many other investors looked to him as the leader of a movement and would only sell if he did first.

Gill’s X account lay dormant for nearly three years. But on Sunday, the cartoon of a man sitting upright seemed to signal that he was once again ready to jump into the investing fray and rally fellow traders into another mission. The image accrued 14 million views and 77,000 likes in 15 hours. The next morning, he posted several more memes from pop culture, including of a resurgent Wolverine (Hugh Jackman) and Breaking Bad’s Walter White (Bryan Cranston) growling, “We’re done when I say we’re done.”

The actual company GameStop hasn’t been performing particularly well. In March, GameStop slashed its workforce and reported lower year-over-year fourth quarter revenue, as it faced continued competition from online retailers and weak consumer spending.

But its stock’s resurgence comes in the midst of a larger spike of activity in meme stocks. Crypto meme coins have seen significant trading volume over recent months, and jumped once again following Gill’s post. Other meme stocks also jumped, including AMC, which increased 22%, and Reddit, which increased 13%.

Speculative stocks typically see increased activity when the economy is strong, and people feel like they have money to gamble with. Many participants in the WallStreetBets craze also felt like they were waging a symbolic war against Wall Street and its control of the financial system. Many individuals certainly made a lot of money. But whether the larger collective mission was successful has been hotly debated. “The whole GameStop thing: they lost,” Kyla Scanlon, an economics analyst and content creator, told TIME last year. “It’s very hard to beat the stock market.”

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