In the 1952 Oscar-winning classic, considered by director John Ford to be his sexiest movie, John Wayne’s retired boxer Sean Thornton makes a pilgrimage to his home village in 1920s Ireland to claim his family estate.

There, he meets his match with Maureen O’Hara’s Mary Kate Danaher and her difficult brother Red, who Victor McLaglen plays.

During The Quiet Man shoot in County Mayo and County Galway, O’Hara suffered from a broken bone in her hand for much of production. In the scene where Wayne kisses her for the first time, she slaps his face.

However, Duke's block caused the hand breakage. And given the film was shot in order, she had to endure the pain without a cast to reset her bone.

To make matters more challenging for the leading lady, she had to whisper a line in Wayne’s ear that he was totally unprepared for.

The scene in question saw the two waving goodbye before the leading lady said an unscripted line to Wayne which resulted in a double-take from him that made the final cut. It's in the movie, but we can't hear whatever outrageous thing she said to get that reaction of out him.

Initially, she had refused to say the mystery words, writing in her memoir years later, “I couldn’t possibly say that to Duke!” However, Ford insisted that the actress do it, so as to get a genuinely shocked reaction from her co-star, which totally worked.

Only those three knew what the line was and took it to their graves. Given that the director considered The Quiet Man to be his steamiest picture, presumably, it was something considered risqué in the early 1950s.

Of course, this scene and the final fight almost didn’t end up in the movie until Ford pushed for the final cut in his usual uncompromising manner.

Republic Pictures had insisted that The Quiet Man be no longer than two hours, believing that audiences wouldn’t want to sit in a cinema for any time beyond that.

At first, Ford refused, claiming he had trimmed all the fat and needed the nine minutes over, but the suits held their ground. So a few days later, he claimed he had the final print ready for screening when really it was his 129-minute cut.

After exactly two hours, the director signalled to the projectionist that the movie be stopped right in the middle of the big final fight between Sean and Red. In the end, the studio executives gave in and let him have his extra nine minutes.