Olivia Newton-John revealed the “Grease” premiere party got pretty wild back in 1978.

Newton-John appeared on Thursday’s “Watch What Happens Live”, with host Andy Cohen asking: “The ‘Grease’ premiere party was held at Studio 54 in 1978, Elton John was there, Grace Jones was there, what do you remember about that night?”

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“I just remember it was crazy,” the actress, who played Sandy in the much-loved film alongside John Travolta’s Danny, replied.

“There were lots of people in the bathrooms doing strange things that I hadn’t seen before. It was wild and fun and a very exciting night,” she added.

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Cohen also mentioned that he’d heard members of the “Grease” cast were “horny,” to which Newton-John grinned: “My lips are sealed.”

The star’s appearance also saw her talk about researching the science behind plant-based medicine such as marijuana and how weed has helped through her battle with cancer. See more in the clip below.