Reportedly, producer
Leonard Freeman clashed with director
Ted Post during production. One day Freeman showed up on the set, issuing orders and taking charge. Post wanted to confront him, but
Clint Eastwood intervened. Eastwood spoke to Freeman, and Freeman left the set and didn't return. What he said was, "If you show up on this set again, there won't be a set ... won't be a cast, won't be a crew."
more