It was one of the biggest tests of Joan Collins’s career.

Would she star in one of the most-hyped films of the era? Or would she have to watch another actress win the role of a lifetime?

But this was no audition room for the actress, then aged in her 20s. It was an industry party in 1950s Los Angeles.

And the “handsy” 50-something who was insisting on whisking her around the dancefloor had no real interest in her performance skills – of that kind, anyway.

This was Buddy Adler, the head of Fox Studios. He made it clear one thing stood between the young British starlet and the lead role in Hollywood’s biggest-budget film to date: 1963 blockbuster Cleopatra.

That thing? Letting him buy her a flat that he would visit “three or four times a week”.

Dame Joan, now 90, recalls: “The very thought of this old man touching me was utterly repugnant. I couldn’t and I wouldn’t.”

So the career-defining role went instead to Elizabeth Taylor.

But did Dame Joan ever regret turning down “the offer”?

“My life would have been completely different,” she tells me over a Zoom call from her central London flat to discuss her new memoir, Behind the Shoulder Pads. “But then I wouldn’t have met my second and third husbands and had my wonderful children.”

There was another advantage: Joan couldn’t stand “heartthrob” Richard Burton who played Mark Antony opposite Taylor. The pair began their relationship on set.

Dame Joan, who had starred with Burton in the 1957 film Sea Wife, says: “He was one of the leading men who thought they had a divine right to sleep with their leading ladies. He told me I would ‘break his record’ if I refused to sleep with him.”

The Dynasty star refused, nonetheless, and she says: “He barely spoke to me for the rest of the production. He was horrible up close – all pimply and pock-marked skin. I never really saw what [Liz] Taylor saw in him.”

Burton, who died in 1984, was far from Joan’s only co-star who would have been cancelled in today’s #MeToo era.

During a love scene in 1970 movie The Executioner, George Peppard “came in for the kill” on a topless Joan, pinned beneath his 6ft 2in frame, kissing her deeply with his tongue.

As did War of the Worlds star Gene Barry and her childhood pin-up Gene Kelly, she says. The latter gets off a little more lightly though as there’s affection in Joan’s voice as she recalls their encounter.

All of which explains why the star, whose goddaughter Cara Delevingne is in the industry, is a fan of intimacy coordinators now hired to oversee sex scenes.

Dame Joan says: “At least actresses won’t have to put up with someone splayed across, slobbering all over them.”

Ironically, it was at one of Singin’ in the Rain star Kelly’s weekly soirees that a certain Marilyn Monroe warned Joan about the studio executives – the so-called “wolves of Hollywood”.

Joan had already had her first run-in with the casting couch in the UK. She was a virginal teen when a seedy producer offered her a lift home, unbuttoned his fly and tried to grab her hand. Now in Hollywood, she was a target for a Who’s Who of the movie industry.

Fox’s Darryl Zanuck “pounced” on her, Jack Warner propositioned her, Sam Spiegel blindsided her with an unsolicited kiss and another producer invited her for a meeting, only to be naked in the bath. Each was rebuffed by Joan’s acerbic wit. These “wolves” were no match for a Paddington-born girl who grew up in the Blitz. She says: “Women of that time were survivors. What really helped me was my father [talent agent Joe] constantly warning me about the pitfalls of the profession. He said if any man gets out of line ‘kick ’em in the nether regions!’”

After losing out on Cleopatra, Joan did one last film for Fox and returned to the UK. She went on to produce and star in The Stud and The Bitch before joining Dynasty in 1981.

● Behind the Shoulder Pads: Tales I Tell My Friends by Joan Collins (Orion, £22) is published today. To order, visit expressbookshop.com or call 020 3176 3832.