According to
Scott Glenn, the original script was about a ruthless club fighter from California with no family and no real background who gets involved in bringing a sword to Japan, and through a lot of crazy adventures he winds up with a martial arts sensei. The core of the movie would have been about father and son finding each other from completely different cultures. After shooting started, Glenn became aware very quickly that all those character-driven scenes were either being cut or shortened to almost non-existence, and that he was doing a martial arts movie.
Toshirô Mifune came to him and told him: "Look, this is what's happening. I'm disappointed, and I know you are, but this is what it is. So you can either have your heart broken every day, or you can use this experience as an opportunity to be spending an interesting time in Japan with me as your tour guide." Glenn accepted Mifune's offer.
