At the center of David Howard’s new true-crime book, Chasing Phil: The Adventures of Two Undercover Agents with the World’s Most Charming Con Man (Crown), is Chicago native Phillip Kitzer, a smooth-talking fraudster who swindled millions of dollars from people and operated across state and international borders.

The book dives into Kitzer's life and tells the story of the young, rank-and-file FBI agents who took him down in the bureau's first-ever undercover investigation of white-collar crimes. (Until J. Edgar Hoover's death, FBI agents were forbidden from operating undercover.) What they expected to be a quick operation ended up dragging on for months, as the agents were drawn into Kitzer's orbit, jet-setting across the globe and building Kitzer's trust before finally wrangling him in the late '70s.

Howard talked with Chicago about how the Chicago con man came across his radar, constructing detailed scenes, and attracting Hollywood buzz.

Chasing Phil revolves around Chicago native Phil Kitzer. Can you tell us about him?

Kitzer was an incredibly intelligent man. He grew up on the South Side with Hungarian immigrant parents. He was a shoeshine boy from a very young age—very entrepreneurial. He moved from shining people’s shoes to selling the shoe shining kits to people. He eventually dropped out of high school in the 10th grade. And after a stint in the military, he taught himself the insurance industry.

When he was starting in the '60s, he went to a bank to get a loan to start his first insurance company, and tried to get a $200,000 loan. The banker demanded a $25,000 kickback, and it was this important moment for him when he realized, “This is how this works.” His formative years in Chicago are a huge part of his story; it’s where he formed his ideas of the way the world works, and the way he was going to make his fortune through financial fraud.

How did Phil Kitzer come across your radar?

I published a book called Lost Rights in 2010. At the end of the book, there's an FBI sting that gained interest among some bureau guys who got in touch with me for signed copies. I ended up having a conversation with a retired agent Myron Fuller, who told me about Phil, and put me in touch with Jack and JJ, the agents pursuing Kitzer.

What was it about his story and the FBI agents pursuing him that caught your attention?

There were two things, really. The story sounded like this amazing, human, road trip story involving these three guys—two FBI agents and a con man—traveling together for eight months. Just how those dynamics played out immediately captured my interest, trying to imagine all the tension built into a situation like that. I also quickly learned it was the first case of its kind for the FBI. They hadn't done white-collar crime cases at all. It broke new ground, and [because of this case,] the bureau established white-collar crimes as one of its top priorities. So, it really was a turning point for the bureau.

The very first time I talked to the agents, they told me they had had no undercover experience and hadn’t been trained in undercover work. They were using their real names and their real credit cards. Dealing with one of the great financial fraudsters of the time, that part of it blew my mind. They were able to walk into this thing basically not having any real idea of what they were supposed to do and how they were supposed to do it, and spend the next eight months pulling the thing off.

Some of the scenes are very detailed in their dialogue. How did you go about constructing these scenes?

There were a number of trials that took place, at least a half dozen, after the operation was shut down. Kitzer testified in all of them, and he had a great memory and told stories in great detail. A lot of the transcriptions contained this very vivid dialogue. I was very lucky that there was so much stuff there in the records. On top of that, this was a big moment in the agents' lives and they remembered a lot of scenes and moments from this experience really clearly. I would compare the two things, overlay them, make sure I had everything lined up accurately.

And you met up with the retired agents in Utah.

Yeah, I started off by getting everyone together. I got Jack, J.J., and also Myron, the three retired agents who lived through this. We all sat down and talked for a few days. It was really great because they would build off each other's memories. One guy would start talking about a scene, and the other guys would add details.

There was a lot of buzz for this book, even before you wrote it, including interest from Warner Bros. and Robert Downey Jr. to turn it into a movie. Did that impact the writing process?

It was exciting and surprising that it happened that early in the process. It took some time to wrap my brain around what it meant. It really got me focused on the task at hand, but it didn't really change anything. I write books, and I was going to do everything I could to write a great one with really vivid characters. Downey’s interest was undoubtedly a cool thing to have floating out there on the horizon.