The life of Jerri Williams, SEPTA's top spokeswoman, took a surprising turn Tuesday when she announced she will step down from the city's transportation authority to pursue her dream of being a full-time crime novelist.

Before leading SEPTA's communications operation, where she's worked the past seven years, she served as an FBI special agent investigating white-collar crime.

Back then, she'd often step back from her responsibilities as a federal investigator and muse creatively.

"And I always would say to myself, 'That's a book, oh, no, no, that's a book. That's a book," Williams said. "And I found one that was really interested and different and edgy, and that's what my first project is about."

"Pay to Play" follows a female FBI agent probing corruption in the Philadelphia strip-club industry. But what's a good crime-fiction novel without some sexual intrigue? In the book, Williams said, the agent is blackmailed by a man with whom she had a fleeting sexual encounter after a night at one of the clubs.

The connection poses a provocative question, she said. "How far will she go to stop him from destroyed her career ... and her marriage?"

A far cry from her day job at SEPTA, it's fair to say. And that's the whole point, Williams said. Once she's out of the 9-to-5 routine, she will have more time to shop the book around. She's doing that now, through an agent, as well as starting on her second novel. With a federal pension and no mortgage payments, she says the lifestyle shouldn't engender too much hardship. 

Williams said readers mustn't leap to conclusions about the protagonists in "Pay to Play"; in other words, none of the characters are based on her own cases.

The book is loosely inspired by a real Philadelphia case from the 1990s in which L&I inspector Frank Antico, who was in charge of adult cabaret enforcement, extorted strip clubs for lap dances, booze and other freebies in exchange for looking the other way. A federal jury eventually convicted Antico with racketeering and extortion, and he was sentenced to a 5-year prison term. 

"I watched two friends of mine, two very attractive female agents, work this case that involved L&I inspector and strip clubs, and I thought, 'This would make a great story,'" Williams said. "I would say it's about 20 percent the actual case and 80 percent my imagination."

Williams' last day at SEPTA is Nov. 25.