Zac Efron is the "furthest thing from a prima donna", according to director Max Joseph.
The 26-year-old actor is currently filming for Max's movie, We Are Your Friends, and has been praised by the filmmaker for his professionalism and chirpy mood.
The Catfish host told MTV: "He's amazing. He isa world-class person. He's the first person to say hello to everyone and he's the furthest thing from a prima donna.
"He's extremely professional, always in a good mood and keeps things light. He loves the crew. He's a trooper, and we have a good time."
Max also revealed that the pair work well together and insists he couldn't have had anyone better than Zac to support him in the making of his first feature film.
He explained: "We talk about a lot of stupid stuff outside of the film and show each other videos about other movies and characters and shots that we like.
"He's just been a great collaborator, and I couldn't ask for anything more from the star of my first feature. He really is bringing everything he's got."
Meanwhile, Max is convinced that Zac's role as a struggling DJ in We Are Your Friends will show fans a different side of the 17 Again star.
He added: "People are going to be really pleasantly surprised. It's a balanced performance, and I think people are going to wake up and say 'Holy s***, Zac Efron!'
"He was funny in Bad Neighbours and great elsewhere, but this movie really steps up his game."
