Development
Film rights were bought by producer Mace Neufeld, who had filmed The Hunt for Red October. A script was written and John McTiernan was originally going to direct Intruder but dropped out and eventually served as an executive producer. The Russian sequences in the film of October had been rewritten at Sean Connery's request by John Milius, and Milius was signed to direct Intruder.
Milius commented about the novel: "It was such an internal examination of that life and what it takes to fly. There was such wonderful reality on life aboard a naval carrier and life in Vietnam. I loved the whole idea of what those guys do".
Milius rewrote the original script. According to Sam Sayers, who worked on the film as technical adviser, "I never saw the first script, but I understand there were scenes of pilots smoking pot and that kind of nonsense. It was unrealistic - Top Gun in Vietnam. Milius just went back to the book. It's the reason he wanted to make the film".
Coonts said that "most books don't seem to survive, but this was an excellent transition. It takes 12 hours to read the book on tape, and it's certainly abridged - 13 flights in the book are scrunched down to four, and the role of the girl (played by Rosanna Arquette) is smaller. But the themes of the film are the same as the book".
Milius said that he was not interested in debating about the Vietnam War, but about "what happens to people, in this case the professionals who fought it, and their reactions as human beings, the institutions that people belong to and give themselves to that are larger than themselves... It certainly is no more patriotic than The Right Stuff, but it's in the same vein".
Milius also added that "one of the things I like about the military, and why I'd have loved to be an officer in the Navy, is that the (moral) code is very simple. I come from a business where there's a preponderance of literature on the lack of morality - and I don't find it terribly entertaining, that atmosphere, in fact I find it rather weak".
The lead roles of the pilots were given to Richard Gere and Brad Johnson; Johnson had just played a key role in Steven Spielberg's Always (1989). Milius talked to Richard Dreyfuss about playing the squadron commander. Rosanna Arquette had the female lead. Gere dropped out and was replaced by Willem Dafoe. Danny Glover played the squadron commander. The film included an early role for Tom Sizemore.
Danny Glover spent five days aboard the aircraft carrier USS Independence for research, which he said made him appreciate the story more: "It's about the camaraderie and the bond of trust that exists between men under stress. The camaraderie and trust I've seen among the men here, many only 18 or 20 years old, in peacetime, has got to be that much stronger under conditions of conflict, especially if they don't feel they're supported from up above".