(CBS News) As a Chicago police officer, Shannon Spalding worked undercover in some of the toughest parts of the city — only to discover some of the most dangerous criminals were fellow police officers. She risked her life to stop them.

Soon after joining the Chicago Police Department in 1996, Spalding drew an assignment in one of the most violent neighborhoods in the city. “It was a full-blown war every single day,” she said.

“It was like a movie set. I was shocked. It was shock and awe for me. It was just a completely different world,” she explained to “Whistleblower” host Alex Ferrer in the series’ second season premiere airing Friday, May 24 at 8/7c on CBS.

To survive, Spalding leaned on veteran cops like Ronald Watts.

“I thought he was battling crime and he was doing it with finesse and grace,” she said.

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