Is Herbalife really a pyramid scheme worth a USD 1 bn short? That’s the position hedge fund manager Bill Ackman has taken — and the subject of the riveting documentary Betting on Zero. On a tip from a Bloomberg reporter, Ackman’s Pershing Square Capital dug deep into the business model of multi-level direct marketing company Herbalife. He was sure that the company, whose revenues reached USD 3.8 bn in 2014, was nothing more than a pyramid scheme. The film details his fight to bring the company to the attention of regulators, his attempts to dodge accusations of market manipulation, and a battle with arch rival Carl Icahn, who attempts to squeeze Ackman’s short.

The company’s revenues derive mostly from distributors signing on and finding more distributors to buy Herbalife products in the hope of roping more distributors under them. The film explores Herbalife’s shady marketing practices which target poor immigrant communities, unable to report the scam. It also looks into attempts to file class action lawsuits by some of the victims who have been burned in the operation designed to only see a small portion of distributors making money.

You can catch the documentary on Netflix or watch the trailer (runtime: 2:02).