The producers turned down the superb but sometimes difficult actress for the co-starring role of the social worker who has a powerful effect on Sidney Poitier, who was cast as a black militant. Poitier had lobbied for Hackett in the role.
Hackett was initially set to play the lead female role but was replaced by Anne Fancis due to clashes with the producers.

Did you know that Joan Hackett was not the only choice for this movie?
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