The Beatles legend was reunited with his long-lost bass guitar after more than half a century apart.

In 2018, a quest began to locate the instrument, which was believed to have been stolen around the the band recorded Let It Be in 1969.

This search, led by the guitar's manufacturer alongside a husband-and-wife journalist duo, evolved into a crowdsourcing effort known as The Lost Bass Project.

Incredibly, the team was able to track down their quarry.

"Following the launch of last year's Lost Bass project, Paul’s 1961 Hofner 500/1 bass guitar, which was stolen in 1972, has been returned," reads a post on Paul's website.

"The guitar has been authenticated by Hofner and Paul is incredibly grateful to all those involved."

The hunt came to a close after sound engineer Ian Horne contacted The Lost Bass Project to explain the guitar had been stolen from his van in London in 1972.

After the Lost Bass Project posted this tip, an email arrived from an unnamed person who said their father had stolen the bass, not realising how valuable it really was.

That thief went on to swap the guitar with a publican in exchange for some beers and a few pounds.

Finally, the publican's daughter-in-law contacted the project to let them know the guitar had been in her attic for some years, and the mystery was solved.

While Paul paid roughly USD$37 (£29), the guitar is now estimated to be worth USD$12.6 million (£10 million).