By David Spunt

PHILADELPHIA (CBS) — The click of a keyboard is one of just a few sounds you’ll hear coming from former FBI agent Jerri Williams’ office. Another sound is a series of podcasts she’s recorded about her stories fighting crime.

It’s catching on. For three days this week, the podcasts were number one on the new and noteworthy list on iTunes.

READ MORE: 2 Suspects Fatally Shot During Home Invasion In South Philadelphia, Police Say

“I was shocked. I have no idea why they selected my podcast but I am so grateful,” Williams said.

Williams joined the FBI in 1982. She left in 2008 before taking over as the chief spokeswoman for SEPTA. She left that job last summer. Williams insists she loved it, but full time writing called her name.

She officially started her novel in 2007. “Pay to Play” is about a female FBI agent investigating corruption in the Philadelphia strip club industry. It’s loosely inspired by the Frank Antico case from the late 90s. Antico was a former L&I inspector convicted of extortion.

READ MORE: Melanoma Isn't Just Caused By Environmental Factors Like Sun Exposure, New Research Says

“I thought, this needs to be a book and so I wrote one,” Williams said with a smile.

Now, Williams is already typing away at her second novel. It’s inspired by a Philadelphia Ponzi scheme from the 1990s.

Williams says the podcasts will continue. She says it’s a way to talk about the mysterious world of the FBI and Philadelphia crime.

“There is a lot of really great case history and case material for writing. The feedback that I’m getting from people is they really love the podcasts and it’s wonderful,” she said.

MORE NEWS: Pennsylvania Lawmakers Want To Pass Red Flag Gun Law To Help Battle Mental Health Crisis

Williams started with just a few hundred listeners last week, now she’s approaching more than 20,000 and the podcasts are still on iTunes.