In January this year, something very strange happened on the US stock market. The shares of GameStop, an unfashionable high street games store, suddenly went through the roof and kept rising. As a result, a group of hedge funds unexpectedly found themselves losing millions of dollars. The giant price spike turned out to be the work of a committed band of amateur online investors – many of whom were out to get their revenge on the titans of Wall Street for the financial crash. Mayhem on the markets ensued. So was this a David versus Goliath clash as many claim? And if so, who really won? James Clayton meets the investors who made a fortune trading from their bedrooms, the tech supremos who were watching on astonished and the hedge fund giants who are now nursing their losses.