A search has begun for Paul McCartney's original bass guitar.
The Beatles star bought the Höfner 500/1 Violin Bass in Germany in 1961, but it disappeared eight years later when the group were recording the 'Get Back/Let It Be' sessions.
It has not been seen since.
The bass was played on Beatles tracks such as 'Love Me Do', 'She Loves You', and 'Twist and Shout' and in venues around the world such as Liverpool's Cavern Club.
The Lost Bass Project have described the mission as "a global search dedicated to tracing the bass- and solving the greatest mystery in the history of Rock and Roll".
They describe the instrument as the "most important bass in history".
The project is being lead by Höfner's Nick Wass who worked closely with Paul McCartney's team and wrote a book about the missing instrument.
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