According to the film's director Scott Hicks, Efron is certainly a fully fledged, grown-up actor.
"He's a hard-working, committed actor, very committed to his craft and I just thoroughly enjoyed working with him," he said.
Also at the premiere was Efron's co-star Schilling. She also had nothing but praise for the actor, whom she called a "goofball."
"It was a blast," she said. "We never took ourselves too seriously. The work, yes, but we were fooling around the whole time."
"The Lucky One" hits U.K. theaters on Wednesday, May 2. It was released in the U.S. on April 20.