The 24-year-old revealed that he couldn't believe he had landed the job when speaking to ITV1 breakfast show Daybreak.
> Zac Efron, Nicole Kidman in 'The Paperboy' - first look pictures
Efron said: "It was everything you dreamed of. She was such a lovely person. I pinched myself every day, especially after doing love scenes with Nicole Kidman. Nicole is so gorgeous!"
Despite her sex symbol status, the actor admitted he was also in awe of Oscar winner Kidman's acting skills, adding: "Nicole was something else and was always in character.
"She didn't get weird method, like some actors do, but I have never seen anyone so centered."
Former High School Musical actor Efron has dated co-star Vanessa Hudgens and has been linked to Mirror Mirror's Lily Collins and his Dr. Seuss's The Lorax colleague Taylor Swift.
He added: "[I hope my wife will have] a sense of ambition and a sense of freedom, which is a careful mix.
"You have to balance those two. I haven't exactly found it yet."
> Zac Efron donates clothes to underprivileged teens
Watch Zac Efron introduce The Lucky One TV trailer below: