Elizabeth Holmes fooled a lot of people. The Theranos founder promised to revolutionize health care with a pinprick of blood and ended up indicted on charges of defrauding investors and deceiving patients and doctors.

She was found guilty of fraud earlier this year and just sentenced to more than 11 years in prison .

In the HBO documentary The Inventor: Out for Blood in Silicon Valley , viewers can see how she was able to convince journalists, venture capitalists, White House officials and military generals about her supposedly revolutionary new blood testing invention a portable box she said could swiftly run hundreds of tests on just a few drops of blood before her lies started unraveling and her $9 billion company cratered .

It is easy to disbelieve Holmes grandiose promises as an outsider watching the documentary. Whats fascinating about the film is seeing Theranos employees who knew Holmes machine was not able to accurately perform blood tests as she claimed, but who in many cases continued to try to develop it and believe in Holmes vision.

But hers is not an unusual kind of psychological con being pulled on employees. Other corporate leaders also use manipulation tactics to retain workers and get them to toe the company line. And these tactics are things employees everywhere need to watch out for.