Nearly a decade ago, an army of bankers, lawyers and traders ditched their regular day jobs to become experts on Libor — the London Interbank Offered Rate.

Libor was seemingly an innocuous estimate of what banks would charge to borrow from one another. However, it was plagued by scandal. In 2012, some of the world’s largest banks were found to have manipulated the rate, submitting artificially high or low quotes to move Libor. Only a couple of people were ever punished, including Tom Hayes, who asserts he has been made a scapegoat and is trying to get his conviction overturned.