The return of day trader Keith Gill, known as 'Roaring Kitty,' has sparked a surge in meme stocks GameStop and AMC. GameStop's stock soared by 70% in one day, hitting a 52-week high at $30.45. However, the stocks faced sharp declines after the initial rally, with GameStop plummeting by over 65% from its high. The meme stock frenzy, fueled by Roaring Kitty's social media activity, has led to significant market volatility and losses for short sellers.