When news broke that Steven Spielberg would direct an adaptation of the WWII-set young adult novel “War Horse,” many expected him to pick a known teen star for the lead. Instead, he went with a relative unknown, 20-year-old Jeremy Irvine.

Irvine, who spent a year at the London Academy of Music and Dramatic Art, had done a few stage roles (including a smaller part in the Royal Shakespeare Co.’s short-lived “Macbeth” update “Dunsinane”) and the Disney Channel U.K. sketch series “Life Bites.”

“Sometimes we get reels from people who think that just doing a bit of Shakespeare in their kitchen works, but he had something to say. He wasn’t just doing the lines,” says Irvine’s agent, Stephen Hatton. Knowing Spielberg was busy setting up “War Horse,” Hatton sent Irvine to meet the director and audition for the part of Albert. “He does make a great impression when he comes into the room,” Hatton says.

Spielberg must have agreed, casting Irvine himself. “Jeremy is a natural actor and a fine young man — a combination that should serve him well as his career continues to grow,” the director says.

Up next, Irvine plans to shoot “Now Is Good” in the spring.