JOHN'S ROCK STAR REBOOT

JOHN TRAVOLTA has been teaming up for fun singalongs with Ringo Starr and it's given him a new lease on life as he eyes a stunning new chapter in his career, sources say.

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"John has a fantastic voice and the moves to go with it — which he proved in Grease and Saturday Night Fever — and people are genuinely glad to see him get out there and flex his talents again," says an insider.