Efron, 30, talked about the memorable incident while he was on Britain's The Graham Norton Show Friday to promote his new movie The Greatest Showman.
Efron recalled being at dinner with his High School Musical director Kenny Ortega when the phone rang and Ortega handed it to him, saying it was Jackson. Efron said he introduced himself as an actor and admitted he rambled on about how big an admirer he was of Jackson's. The encounter ended with Jackson asking Efron to put his friend Ortega back on the phone.
However, a few minutes later, Jackson called back, apparently after realizing who Efron was. He told the younger artist he loved what he did and was a big fan of High School Musical. Efron said the compliments from his idol caused him to break into tears.
He went on to say he thanked Jackson for not only inspiring him, but also showing him how to dance, believe in himself and "shine."
"That made him cry and we were both crying to each other on the phone," Efron said. "And he ended the whole phone conversation with something along the lines of, 'Hey, Zac.' And I stopped crying for a second. He's like, 'Isn't it awesome?' And I was like, what? And he goes, 'Dreams really do come true, don't they?' And I was like, Michael, you can't say things like that. You're killing me, man!"
Jackson died at the age of 50 on June 25, 2009. Ortega directed a film called This is It featuring Jackson preparing for what was supposed to be his final concert residency in London.