In 1965, Nathanson wrote the war novel The Dirty Dozen, a story about 12 servicemen, convicted of robbery, murder and rape, who are sent on a suicide mission to blow up a chateau of German generals just before D-Day with the promise of commuted sentences to those who survive.

The novel was inspired by the supposedly true story of World War II criminal soldiers who got the nickname "the Dirty Dozen" (or "Filthy Thirteen") for their refusal to bathe and who were said to have been sent off on a similar mission. Nathanson heard the story from his producer friend Russ Meyer, who said he learned of the tale while working as a combat photographer during World War II.

Although Nathanson researched in vain for two years to verify the story's accuracy, he still received a contract for a book. He and his editor fictionalized the story. The best-selling novel sold more than two million copies was translated into 10 languages and made into a hit movie in 1967 starring Lee Marvin, Charles Bronson, Jim Brown and Donald Sutherland. In the movie, while the mission is shown in detail, in the book it is just an appendix - a sudden and shocking denouement which totally wrong-foots the reader.