A collection of 200 previously unseen photographs showing John Lennon on the set of 1967 movie How I Won the War is offered at Omega Auctions.
The photographs depict him in a relaxed mood; playing cricket and laughing with the crew and his co-stars.
The set is valued at £30,000-40,000 ($42,319-56,425) ahead of the March 22 sale in Liverpool.
Karen Fairweather, director of Omega Auctions, told the MailOnline: "These are really rare photographs that show John Lennon just messing around and having fun.
"It was at a time he didn't know what he was going to do in the future and he thought The Beatles were coming to an end…
"He just looks so happy and relaxed which is quite rare to see, he was very intense - but you just don't see that in this collection."
During downtime on the shoot Lennon began writing Strawberry Fields Forever, one of the Beatles' most iconic songs.
Last month Paul Fraser Collectibles bought a lock of Lennon's hair, cut at a barbers in Munich just days before he started filming.
The sale will also feature a copy of an original Beatles demo record. It carries an estimate of up to £20,000 ($28,186).
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