Michael Burry, the Wall Street trader who predicted America's subprime mortgage crisis in the 2000s, the spark which ignited a global financial meltdown, has made a bet against the S&P 500 and Nasdaq 100 stock indices, according to filings with the Securities and Exchange Commission, the American financial regulator.
Mr Burry's firm, Scion Asset Management, has bought $866m in "put options" against a fund that tracks the S&P 500, the American benchmark index. These give investors the right to sell shares at a fixed price in the future and means that he could make a profit if shares fall.
The firm has also bought $739m in bets against a fund that tracks the Nasdaq 100, which follows some of America's largest technology companies.
Such is his conviction, Mr Burry is using more than 90pc of his fund's portfolio to bet on the downturn, according to reports.
The hedge fund manager first rose to fame with his bets against the American housing market before the 2008 financial crisis, a move that netted his investors hundreds of millions of dollars in profits.
His actions were chronicled in Michael Lewis' book The Big Short, and later made into a film in which he was portrayed by Christian Bale.
Mr Burry is known to be an eccentric character on Wall Street. He has a glass eye as a result of suffering a rare form of cancer as an infant and his success is often attributed to a strong ability to focus.
Before joining the fund management industry, Mr Burry studied economics and pre-med at the University of California, and later earned a medical degree.
Although he is not a practising doctor, he has kept his licence as a physician active with the Medical Board of California.
The S&P 500 is up by around 15pc in the year to date, while the Nasdaq 100 is up almost 37pc over the same period. Most of these gains can be traced back to only a handful of companies, such as the chip-maker Nvidia.
US stocks have gained this year
Comment: That was a tweet, in this instance he has allegedly bet 90% of his portfolio's funds.
At the end of The Big Short, it was noted that Mr Burry's investing had become focused on "one commodity: water".
However, by 2019 he told Bloomberg he had sold out of these investments to focus on stock picking and recommended investors look at smaller companies in Japan. Mr Burry also expressed concern over what he viewed as a "passive investing bubble".
"Trillions of dollars in assets globally are indexed to these stocks," he said. "The theatre keeps getting more crowded but the exit door is the same as it always was."
Robert Kiyosaki, the author of the self-help best-seller "Rich Dad Poor Dad", suggested this week that both Mr Burry and the famed investor Warren Buffett were waiting for the stock market to crash.
"I just watch these guys waiting for the market to crash then go back in," Mr Kiyosaki told Fox News. "It's a lot of money sitting on the sideline right now."
Mr Buffett's Berkshire Hathaway fund has sold billions of dollars in stocks this year, ramping up his holdings in cash and short-term "cash equivalent" Treasury notes to more than $140bn.
These reserves can be deployed to buy shares cheaply after market falls.