Denzel Washington and Lymari Nadal as Eva in American Gangster David Lee/Courtesy of Universal Studios

"Absolutely," is the director's answer. "You have to have it all, because these two people are going to function basically by themselves as two leading characters where they haven't got each other to play off. That isn't going to happen until 20 minutes from the end. So from my point of view and the balancing act I have to do, I've got to make each universe so rich so you are very satisfied to sit there and watch that section evolve and move on. [You depict] Frank going to Vietnam, and you suddenly cut to a park and see a guy walking his wife and kid. And he's got a roving eye, and he's being told that he hasn't got any room in their life. That's a great dynamic. That makes you pay attention."

With the script in place and Scott on board, wooing Washington back to the project was not difficult, even though he had previously been tapped as a possible director.

"I wasn't hesitant at all. A good story is a good story. I just think that before Training Day, I hadn't really been offered that kind of role. After Training Day, that was all I was offered," Washington laughs. "No, that's not true, but I was offered more of that kind of thing. But it just comes down to good material, great actors to work with and a great filmmaker. It wasn't that complicated."

It also helped that Lucas's story was obviously very close to Washington's heart.

"This is a Harlem story. This is about a guy who was a kingpin, but a different kingpin… Maybe it is cliché, but I think there was more honor among thieves in those days. There was a sort of cult of ethics. We didn't hear about Frank killing kids and drive-bys and all of that. He's a very interesting man. He was very much a family man, and believed in sitting down at Thanksgiving with the family. He was in the drug business. I don't think he looked at himself as a killer or even a criminal. He was in a business, he sold the product, and he did a good job at it."

Both Brad Pitt and Crowe were considered for the role of Roberts, but Scott had, obviously, established a great working relationship with Crowe on films like the 2000 box-office smash Gladiator and the drama A Good Year. And Washington and Crowe had paired up once before in the poorly-received 1995 sci-fi thriller Virtuosity, with Washington playing the role of a police officer tracking down Crowe as the villain.

"Wonderful movie," Crowe says with a broad playful-yet-sarcastic smile. "Just a momentary lapse, wasn't it? We were both young then, young and innocent."

And although they may not rank the film among their best, it had presented them the opportunity to act together.

"I heard that Denzel was happy with the idea of doing [American Gangster] with me, and obviously, I was happy that I was doing it with him. So we didn't talk about [Virtuosity] until we were on the set. 'Hello, mate. How you doing? Good to see you again.' And we were shooting that day."