Some people can make money. Other people can't. It's a thought that makes William Leith wake up in cold sweats.

He doesn't know why it makes him feel anxious. After all, money isn't real. We created it. Humans did. It's our masterpiece.

But the desire for it is killing us.

It is this dilemma that sets William Leith off on an adventure into the bizarre, morally dubious yet highly desirable world of the mega-rich.

He spends a day with the real-life Wolf of Wall Street who, not content with his hundreds of millions, devised a fraud so he could make hundreds of millions more. He visits a Baroque mansion where a Russian half-billionaire lives alone with his butler. He tours the estate of Felix Dennis, the maverick tycoon who commissioned an avenue of statues to tell the story of his life. He flies to private islands on private jets, meets private men in private clubs, experiencing the dizzy highs of a life without limits - but all it does is give him crippling anxiety.

Throughout it all he asks himself: what makes these people wealthy? And how come I'm not?