Photo: Getty Images

By Kathleen Perricone

Ethan Hawke stars in Boyhood, a movie that follows the life of a young man as he grows up from the ages of 5 to 18 … and to make it as authentic as possible, it was actually filmed over the span of those 12 years.

“We did a little big every year,” the actor explained when he called in to On Air with Ryan Seacrest on Friday morning. “I went to Austin and we’d rehearse and workshop and meet the kids again and see what was going on in their lives … we’d shoot for three or four days and then I’d go away for a year. And we’d find time to meet again the next year.”

Ethan, 43, joked that when writer-director Richard Linklater first told him about his lofty plans, “I remember thinking that’s a really cool idea, but hasn’t some German or Russian done that back in 1968 or something? But no.”

Boyhood is in theaters now.