Originally developed as a film for Robert Mitchum. After Mitchum, James Coburn was attached to star- but that fell through as well. Having already invested in the script, American International Pictures decided to turn it into an "urban picture" and cast a black actor. Dick Anthony Williams, best know for his work in The Mack (1973) and Slaughter's Big Rip-Off (1973) was initially cast, but was quickly replaced by Isaac Hayes, who wanted to get into acting. It was also felt that Hayes was a bigger name draw than Williams.
This film was Nichelle Nichols only entry into the blaxploitation genre. She declined all offers for other blaxploitation films only to concentrate on the science-fiction convention appearances--especially "Star Trek" conventions--and later as a recruiter for NASA.
Yaphet Kotto only agreed to play Harvard Blue because he was going through a divorce at the time and needed the money.
Scatman Crothers had to use cue cards on account of the fact that he had trouble remembering his lines.