Sam Boggs is an explosives expert for the CIA.
Boggs is certainly not an agent. Not for the CIA nor any other organization. He is a bomber. He was an ex-Berkeley chemistry professor, ex-radical, bomb-builder-for-hire. Travelling around Europe as the US wanted him for old crimes, he made a fair living making bombs for whoever wanted one. His only requirement was that it could not cause loss of life. Blow up as many buildings as you wanted as long as no one got hurt, and Boggs was the man to make highly reliable explosives.
In the mid 60s, Boggs had been an associate professor at Berkeley teaching chemistry and specializing in the new world of plastics. He was engaged to Susan, a graduate student determined to make her mark making the human genome and curing disease. Then Boggs was approached by the U.S.military who wanted bombs designed from plastic so the shrapnel would not be detectable by current medical means thus making them more effective. As he worked on it, his fiance grew more radical and took him along with him until he decided to stop work and take up the revolution cause. Then his girl left him to take a high paying research job and Boggs was left with a radicalism he really didn't believe in and the police after him.
What followed was over ten years of building bombs around the world but for money, not for belief. He has grown tired of it and knows that it is just a matter of time before some radical zealot ends up getting Boggs killed. He is no longer a young man and he has found a beautiful, sexy young companion to make his days exciting. He doesn't want to make bombs anymore. That, naturally, is when the deal of a lifetime comes up and Boggs has to make a decision about the rest of his life.
Boggs is a die-hard anti-hero. He would be the first to insist on that. Then, however, thousands of lives are put in the balance and he has to prove how heroic he can be.