They are a rag-tag bunch, often working from home or tiny offices scattered round the world, from rural Texas to Beverly Hills and a suburb near Australia's Bondi Beach.
Some have never even been to China; most don't speak or read Chinese.
And yet in the nine months preceding August, this small group of "short sellers" published research exposing accounting fraud at a series of Chinese companies listed in the United States and Canada, and made as yet unproven allegations against a whole bunch more.
As a result they ended up scuttlIng a once hot sub-sector of the American capital markets.
In a number of cases they claim to have made a killing by shorting those stocks - placing a bet that the shares would fall in value - before publishing the research.
They insist they operate independently but are clearly influenced by one another's ideas and tactics.
Altogether, they have been the catalyst that has wiped more than $21 billion off the market value of Chinese companies listed in North America.
The sell-off has led to big losses for some very prominent investors, including hedge fund manager John Paulson and former AIG CEO Maurice "Hank" Greenberg.
In the aftermath, a series of companies have been delisted by US exchanges, auditors have quit at a number of others, investors are filing class action lawsuits, and the US Securities and Exchange Commission is pursuing investigations.
To their supporters, the short sellers are doing the regulators' work for them by exposing fraud.
They argue that many of these companies, which are often legally domiciled in offshore havens such as the Cayman Islands, should never have been allowed to list in America in the first place.
To their detractors, the short sellers have leveraged a handful of correct calls on accounting shenanigans into a campaign that has tainted many legitimate Chinese companies.
Some accuse them of conspiring with big hedge funds to take short positions before they publish their research.
Many have jumped into the Chinese short-selling game; Reuters has identified the five below as among the most prominent players.
Image: U.S. Treasury Secretary Tim Geithner shakes hands with China's State Councilor Dai Bingguo after their closing statements during the U.S.-China Strategic and Economic Dialogue at the Interior Department in Washington May 10, 2011. REUTERS/Jason Reed
Text: Daniel Bases, Ryan Vlastelica, Clare Baldwin and Mark Bendeich, Reuters