In 1983, at age 25, Mark Whitacre earned a Ph.D. in Nutritional Biochemistry from Cornell University. At age 32 he became president of the fastest-growing division within Archer Daniels Midland, one of the largest conglomerates in America. At age 40 he entered prison and became a Christian there. At age 49, in December 2006, he left prison.

Whitacre is best known publicly for his whistleblower role in the 1990s ADM price-fixing case, which ended with a $100 million fine for the company and prison for some top officials. ADM's 2005 annual report also lists a $400 million payment to settle a class action suit. But Whitacre, while secretly taping price-fixing discussions, was also stealing $9 million from ADM.

His saga of corruption and mania will receive new attention over the next several weeks as The Informant!, a movie starring Matt Damon as Mark Whitacre, hits theaters around the country. (See "Unfaithful telling," Sept. 18, 2009.) The film is a dark comedy that does not deal with Whitacre's conversion to Christ-and that's a remarkable story of how hard time created receptivity to God's good news. Whitacre told me that had he avoided prison or received only the six-month sentence that could have been his at one point, he would have remained merely a nominal churchgoer who worshipped financial success.

Here's an edited transcript of our interview:

Q: Why did you join ADM in 1989? I was hyper-ambitious and almost over-compulsive. Career was everything to me. ADM made me the youngest divisional president in the history of that company.

Q: ADM turns corn into ethanol and hundreds of food products, right? If you go to the grocery store today you'll have a difficult time buying food that doesn't have something from ADM in it.

Q: You learned soon that the company was involved in price-fixing. Yes, but not in my division, at first.

Q: Why is price-fixing a problem? You think that sales people are out there competing, one company against another, but in reality upper management is making deals with competitors in order to drive the prices up. You're ripping off from consumers billions of dollars a year.

Q: Free markets work well because they're based on competition, and this was a way to eliminate competition. Exactly. It's deception, and it takes away the free market.

Q: Your personal venture into deception began in 1991 when you responded to one of those scamming letters from Nigeria. There wasn't even email then, it was by fax, and it was new. They made all these promises that we would make $20 million, $30 million, $50 million. Being hyper-ambitious, over-compulsive, I invested, along with a couple other vice presidents under me.

Q: When you lost $200,000, how did you respond? I wrote a check to myself from ADM.

Q: You submitted phony invoices? That's correct.

Q: As a divisional president you had check-writing authority. Yeah. I knew about the price-fixing which was a billion-dollar crime, so I sure wasn't worried about the company turning me in for a $200,000 crime.

Q: By 1992 your division was involved in the price-fixing, but you were having trouble with a big manufacturing plant and made up a story about sabotage. How could our competition be sabotaging our plant? We had all these price-fixing deals going on. They were our friends.

The FBI came to check out the sabotage claim. My wife Ginger asked, "Why are you so nervous about the FBI? Just tell them what's going on and it shouldn't be a big deal." And for the first time I told her, "There are things going on in the company that I've never told you about."

Q: When you told Ginger about the price-fixing, how did she respond? She said, "Gosh, that's wrong. That's ripping off every consumer out there." She put her foot down and said, "I'm going to tell the FBI what's going on."

The FBI agent came to our house. My wife stayed really close by to see if I was going to tell them everything. She said that if I didn't tell them, she was going to. I went along with what I was coached to say. The FBI agent was ready to leave the house. She stopped him and said there was a lot more to say than what I was telling them.

Q: Under pressure from Ginger, you confessed. I met for another four hours with the agent and told him everything that was going on in the company. I became the highest-level executive to turn whistleblower in U.S. history. It was because of my wife doing the right thing.

Q: What was it like to wear a wire? I would meet with the FBI at 6 a.m. They would shave my chest and hook microphones up on my chest-also a backpack mike, one in my briefcase, one in my notebook.

Q: Meanwhile, you're embezzling more. I started worrying about a financial blanket for my family if I lost my job. That's when it became in the millions.

Q: While all this is happening you're going to church every Sunday. My family went to the Methodist church. I considered myself a Christian. People saw our 13,000-square-foot house, our 8-car garage full of cars. People would say, the Whitacres are behind these iron gates, they've got horse stables, they've got everything. We really had nothing-or at least I didn't.

Q: You had a triple life: loyal employee, secret agent, embezzler. That's correct. Building this company during the day, but at night I'm meeting the FBI agents two or three times a week at midnight. I'm giving them all these tapes and I'm making tapes every day, tearing the company down.

Q: Psychological pressure. I would come home and my wife would say, "Who'd you work for today? ADM or the FBI?" I started working for myself. I was into seven-figure compensation, and that's a lot for a young man coming in at 32, seven years out of grad school. I got carried away with that.

Q: And ADM had something on you. As soon as the company learned that I was an informant they told the FBI that I was also embezzling on the side.

Q: Your lawyer made a strong case for you to get a minimal sentence. Right. He argued that my crime was a $9 million crime but I resolved a billion-dollar crime with the tapes that I made. He thought there was a good chance that I would get about a six-month sentence in the end.

Q: You didn't take that deal. In the state of mind that I was, I just couldn't even accept it if he offered me probation. With the education and the drive that I had, to be a felon-I just couldn't accept that in my mind or in my heart at that time. So I fired that attorney.

Q: Is that because you were justifying yourself? I never looked at it as embezzlement during that time. I had a sense of entitlement. I wore a wire in Hong Kong, in Paris, in Mexico City. I'd have to run from the meeting in Paris, meet the FBI agents at the embassy, give them the tapes, and run back to the meeting to have a dinner meeting with the competitors.

Q: Ego? I looked at it as paying myself. I am solving a billion-dollar crime for the FBI. They are going to get hundreds of millions of dollars in fines paid to them, what's $9 million?

Q: Do you think other executives justify themselves similarly? Enron, WorldCom, most of those people are good people in their community, but you get this sense of entitlement. You don't look at it as a shareholder's company. You don't look at it as a public company. You look at it as your company. I looked at ADM as my company. I can pay myself what I want. It's my company. I will be the next president.

Q: So in 1998 you received a sentence that would keep you in prison until at least 2006. I started thinking, "How am I ever going to get through?" I did not want to live. I did not want to put my family through it. I tried to kill myself.

Q: Your thinking changed in Atlanta. I was being transferred through this Atlanta holdover that was 23-hours-a-day lockdown. They put your meals through the door, that type of thing, three times a day. One prisoner had 30 years, another almost life. Everyone was let out for an hour a day in what I called a dog cage, this crowded fenced-in area.

Q: Dangerous place, and you didn't want to go. They took the hour break. I did not. I was reading the Bible, reading in Psalms, and that's when I started really relying on God, as compared to going to church on Sunday and saying I'm a Christian. I got on my knees and said, "God, for someone in prison for almost a decade, the divorce rate is over 99 percent. They don't survive as a family six months in prison, let alone a decade. Would I even have any employment after nine years in prison, a convicted felon?"