GameStop’s shares slumped by 40% in 25 minutes on Wednesday, after a few days of frenetic growth.
Earlier that day the share price had soared to nearly $350 (£250) – 100 times more than this time last year.
What does this tell us?
One of the wildest stories of the year is still very much alive
Many amateur traders are still both making money – and getting hurt
Our understanding of what happened in late January, when GameStop’s share price was making headlines around the world, remains incomplete
Why is it shocking?
In February, the prevailing attitude on Wall Street was the share price was slowly finding its natural position.
It had fallen to about a 10th of its late January market high.
And that spike was widely thought to have been a one-off – hedge funds would never again allow themselves to be blindsided.