PROVIDENCE, R.I. (WPRI) -- One of the most brazen heists in U.S. history took place 50 years ago Thursday when a gang of daring thieves broke into a secret Mafia vault hidden in a Providence fur storage facility.

What they discovered inside that secret safe deposit room would trigger the longest, most expensive criminal trial in Rhode Island's history. Equally as intriguing as the crime itself is the enduring mystery as to what happened to the lead gunman who led the heist.

In the video above, Target 12 investigator Tim White takes you inside this extraordinary true crime saga, revealing details about the day that shook the underworld forever. He is coauthor of the book "The Last Good Heist," which chronicles the robbery.

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