-- GameStop and AMC rose in early U.S. trade on Tuesday as a rally in so-called meme stocks spilled over into second day, after a key figure in their 2021 rally re-emerged after an extended break on social media. 

GameStop (NYSE:) and AMC Entertainment (NYSE:) both soared, piling on to gains of 74% and 80%, respectively, on Monday.

Other stocks, including the U.S. shares of BlackBerry (NYSE:) and headphone maker Koss Corporation (NASDAQ:), surged. (NYSE:), which had fostered a bulk of the 2021 meme stock frenzy on its Wallstreetbets forum, gained, as did (NASDAQ:), which reported bumper retail trading volumes during the craze. 

The spike in stock prices had little to do with the fundamentals of the companies, and came after Keith Gill, who goes by the social media monikers "RoaringKitty" and "DeepF***ingvalue", posted a series of cryptic images and gifs on the social media platform X. They were the first posts from the account in nearly three years, and did not mention GameStop. 

The posts included clips from movies including Pirates of the Caribbean, Tombstone, V For Vendetta, and a comic of a man sitting up in a chair. The image, which was the first of Gill’s new posts, is used to convey the message that things are getting serious. 

In 2021, Gill’s posts on Reddit, particularly regarding Gamestop and the overwhelming amount of short positions against the stock, spurred a flurry of retail buying into the video game retailer.

Buying then spilled over into other stocks with relatively weak fundamentals and high short positions. This, in turn, spawned the idea of meme stocks -- shares which move largely based on social media sentiment, rather than the actual fundamentals of the company.

But despite Monday’s gains, Gamestop, AMC and the other meme stocks remained well below peaks hit during 2021. Gamestop was trading at about $49.58 a share as of 09:46 ET (13:46 GMT) -- a fraction of the $120 hit in early-2021. 

Ambar Warrick contributed to this report.