Producers of an upcoming documentary about Anita Pallenberg have released unseen film of the '60s-era actress and model on vacation with Mick Jagger and Keith Richards in 1967.

The ocean cruise is notable for including the moment Jagger came up with the title "Glimmer Twins" for himself and Richards. Another guest could tell the pair of Rolling Stones were celebrities but didn't know who they were, so asked Jagger to offer a "glimmer" of a clue to their identities.

The footage from Catching Fire: The Story of Anita Pallenberg is accompanied by notes from her memoirs, which were left unpublished when she died in 2017. Read by Scarlett Johansson, they recount Pallenberg preparing to tell Richards that he was to become a father.

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"We were never 'peace and love' kind of people," she wrote, "but we wanted to reassure each other that everything was okay. So we decided to take a trip together: Mick, Marianne [Faithfull], Keith, and I.

"Crossing the Atlantic on a freighter, we must have seemed pretty eccentric to the people on the ship. We had great outfits for strolling down the decks. Beautiful Marianne was always dressed top-to-toe, with long gloves [and] a hat. She was like a Tennessee Williams character – and I was pregnant."

Watch the Trailer for 'Catching Fire: The Story of Anita Pallenberg'

Keith Richards Had Three Kids With Anita Pallenberg

Richards had three children with Pallenberg before their split in 1980. In a separate trailer, he says: "I was bursting with love. ... Anita is in a lot of [my] songs. She's a muse, I'm sure, and not just for me."

He adds: "You’re talking about a one-off here; usually I was just trying to keep up with her ... and most of the time it was fun."

Catching Fire: The Story of Anita Pallenberg is set for release in theaters and digital channels on May 3.

Watch the 'Glimmer Twins' Trip Clip

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