Scammers cheat Americans out of billions of dollars. And many times, the people who lose money, never report it. Now, the FBI is working to change it.

The scam began when a victim was contacted by someone claiming to be with Bank of America’s fraud department, detectives say.

The FBI pored over Jeffrey Epstein’s bank records and emails. It searched his homes. It spent years interviewing his victims and examining his connections to some of the world’s most influential ...