The 77-year-old music legend surprised fans at his 'Freshen Up Tour' concert at the Dodger Stadium when he introduced the iconic Liverpool band's former drummer on stage with him for the first time since the pair performed at the Grammys in 2014.
After performing the group's 1968 hit 'Birthday', McCartney announced: ''We've got a surprise for us, a surprise for you, a surprise for everyone.
''Ladies and gentlemen, the one and only, Ringo Starr.''
The pair then shared a hug, whilst McCartney gushed: ''I love you, man.''
After setting up his drum kit, they treated fans to renditions of 1978 classic 'Sgt. Pepper's Lonely Hearts Club Band (Reprise)', the version which sees Starr start the track by playing the drum part unaccompanied for four bars, followed by a brief bass glissando from McCartney.
They then rocked out to heavy number, 'Helter Skelter' - which McCartney was ''put off'' performing for years because of the song's association with the late cult leader Charles Manson, who was responsible for the murder of model Sharon Tate and four others at the Los Angeles home she shared with Roman Polanski in August 1969.
At the end of the performance, Starr threw his drum sticks into the crowd and then jokingly pretended to offer McCartney's bass to the sold-out stadium.
If that wasn't enough, the Los Angeles crowd also witnessed a special guest slot from The Eagles' Joe Walsh for 'Carry The Weight' and 'The End' from 1969's 'Abbey Road' LP, which features the last recording sessions featuring all four members of The Fab Four - which also included the late frontman John Lennon and guitarist George Harrison.
'Let it Be' hitmaker McCartney ended the epic 38-song set by telling his US fans it won't be the last time they will see him.
He vowed: ''Farewell to you guys. Farewell to America. Only one thing left to be said: We'll see you next time!''
After the concert, the 'Egypt Station' singer posted a picture of him and Starr from the gig, and wrote on Instagram: ''Reunited with my favorite Starr #FreshenUpTour @ringostarrmusic (sic)''
They might sound like they're from the 70s, but they way they roll is very 2020.
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