US conservative groups have pledged to protest at screenings of a film about scientist Alfred Kinsey, who lifted the lid on sexual behaviour 50 years ago.
Liam Neeson plays the controversial scientist in Kinsey
Played by Liam Neeson, Kinsey is blamed by critics for the sexual revolution.
The Generation Life group said Kinsey was partly responsible for "devastating consequences of sexually transmitted diseases, pornography and abortion".
Kinsey writer and director Bill Condon said protesters wanted to "pretend that the last 50 years didn't happen".
The scientist's reports in 1948 and 1953 revealed the truth, he said, about what people got up to - with startling claims about masturbation, homosexuality, prostitutes and even bestiality.
But his methods, conclusions and personal preferences have come up for heavy criticism ever since.
Generation Life head Brandi Swindell said the group would hand out pamphlets and carry placards outside cinemas to try to persuade people not to see the film.
"If this was a true documentary, they would have included more negative information," she said.
"They're sugar-coating the issue, trying to make him look like a genius who all of humanity should be grateful for."
Christian group Focus on the Family said the film condoned immorality.
"To say that it is rank propaganda for the sexual
revolution and the homosexual agenda would be beyond stating the obvious," wrote Tom Neven, who reviewed the film.
But Mr Condon, who won an Oscar for 1998's Gods and Monsters, said protesters were "confusing discussion with endorsement".
He said tried to present both sides of the scientist's character and let people make up their own minds.
"Kinsey was a very complex man, in some ways damaged beyond repair," Mr Condon said.
"He affected everybody's life, and I hope the film gets a little breathing room for people to see it and think about it for themselves."
Kinsey goes on limited release in the US on Friday before being rolled out across the country in coming weeks.