AMC Entertainment Holdings Inc. dizzied investors Thursday by losing 40% of its market value, then regaining more than half of that — and pocketing more than $587 million in fresh cash by exploiting the frenzy.

The stock’s wild rally of 2021 initially collapsed Thursday when the company disclosed plans to sell more shares and use the money to cut its heavy debts. AMC went ahead with the sale anyway, ultimately collecting $587 million by midday, and any concern among investors that their holdings would be watered down faded after AMC said it completed the program.

After briefly erasing all of their losses, the shares closed down 18% at $51.34. The decline continued in after-hours trading, with the stock falling as much as 11%.