Donald Sutherland was part of one of Hollywood’s most notorious controversies

The movie might have been titled “Don’t Look Now,” but viewers’ eyes were wide open for one steamy scene.

That’s because the 1973 supernatural horror film starring Julie Christie and Donald Sutherland, who died Thursday at age 88, included one of the most controversial sex sequences in Hollywood history.

The nookie was so realistically shot, many audience members at the time believed it was genuine. Some still do.

“We did a good job, it’s very real,” cinematographer Anthony B. Richmond said in production notes for a re-release. “People still say they actually made love, but they didn’t.”

In the screen adaptation of Daphne du Maurier’s novella, directed by Nicolas Roeg, Sutherland and Christie play a married couple, John and Laura, who go to Venice after the death of their young daughter.

When a psychic claims to have an otherworldly connection to the deceased girl, Laura’s mood improves and the pair’s passions are enflamed for the first time in ages.

Clothes come off, they inelegantly tumble all over the bed and there are even a few seconds of (simulated) oral sex, which was extremely rare for a mainstream movie in the 1970s.

In his review for The Post, critic Archer Winsten wrote, “I don’t know exactly what it accomplishes, except that no one can call such fancy angles and brilliant cutting mere pornography.”

Peter Bart, who was a Paramount executive at the time, claimed he was on set that day and watched the action unfold.

“It was clear to me they were no longer simply acting: they were f – – ing on camera,” wrote Bart in his 2011 book “Infamous Players: A Tale of Movies, the Mob, (and Sex).”

But Sutherland denied the scandalous claim to the Hollywood Reporter.

“Not true. None of it. Not the sex. Not him witnessing it,” he said.

Later, while promoting the film “The Leisure Seeker,” Sutherland said in a video that the entire process had been clinical.

“We were just alone in the room with Nic and Tony Richmond. Two [handheld cameras] and Nic saying, ‘Donald, put your mouth on Julie’s breast.’”

And Christie, too, later called it “pretend sex.” Though the actress was more enthusiastic about the roll in the hay in a 2015 interview.

“It was just flesh squirming and rolling and touching, and God I thought it was absolutely lovely,” Christie told BBC 4. “I loved the squirming bits and all those things you don’t see.”

Her then-boyfriend Warren Beatty, however, loved nothing about “Don’t Look Now.”

He was reportedly so enraged by whispers about the scene, he traveled from Los Angeles to Europe.

“Warren Beatty flew around the world, trying to get the film killed and prevent it from being distributed,” screenwriter Allan Scott said in the production notes.

Bart wrote that Beatty wanted the scene re-edited, and Richmond agreed with that account, saying the actor wished to “cut that scene, pubic hair by pubic hair.”

There were some edits made — for the MPAA.

Nine frames were cut in order for “Don’t Look Now” to land an R rating in the United States. In the UK, the sequence went unscathed and was rated X — for adults only.

Cunningly, British Lion, the film’s financiers, boasted in a press release that America had “banned” the titillating scene.

Drama is always good for business.