In the Marvel superhero films, the character of the brilliant, bumptious billionaire inventor and philanthropist Tony Stark, also known as Iron Man, is (loosely) based on Elon Musk. Robert Downey Jr, the actor who plays Stark, and Jon Favreau, director of the first Iron Man films, met Musk when they were developing the character. With his bold plans for space exploration, pop star girlfriend and idiosyncratic Twitter feed, Musk certainly has an aura of showbiz about him. That pop cultural appeal may help to explain the remarkable run-up in the share price of Tesla, the company Musk founded and still leads. At their recent low point in March 2020, Tesla shares fell to about US$72, adjusted for last year's stock split, but they then went on a run to above US$880 in January 2021. It was a move that did not seem based on any news that would justify an equivalent change in expectations of the company's future earnings.