'Big' at 30: Former child star David Moscow on being studied by Tom Hanks for role

First things first: David Moscow did not grow up to look just like Tom Hanks.

Still, he was the perfect choice to play the young version of Hanks (or “Small Josh”) in the 1988 body-swapping classic Big.

In a recent interview with Yahoo Entertainment, Moscow, now 43, talked about the life-changing role.

When the young Bronx native first auditioned, it was actually Robert De Niro who was set to star as the boy trapped in a man’s body, with Penny Marshall directing. (Marshall had taken over the project from Steven Spielberg, who was originally going to make the film, cowritten by his sister Annie, with Harrison Ford). Moscow, meanwhile, initially went out for the role of young Josh’s best friend, Billy, who would ultimately be played by Jared Rushton.

Moscow admits his hometown may have played in his favor during the casting process; Marshall hails from the same New York City borough. “Five or six months [after the audition], we got a call,” he said. “When Hanks had switched in, Penny was like, ‘Get me that kid from the Bronx!'”

Though Moscow had the curly hair and innate charm of Hanks, there was still some small measure of physical transformation required: “They had to maneuver me a little bit. So I had to dye my hair, I had to have green contacts, some of my teeth fell out during shooting, so they actually had to put teeth on this flipper brace that I would wear. We fudged it a little bit.”

Moscow, who has retired from acting but still works in the entertainment industry as a filmmaker, producer, and financier, also had to make himself available to his famous costar so that he could nail down the mannerisms of a 12-year-old. And when the film came, Moscow saw himself in Hanks’ Oscar-nominated performance.

“My feet had grown large, and I wore these Converse sneakers, so I kind of walked like a duck almost,” he said. “And that was something that I think he used across the whole movie.”

Hanks also clearly observed Moscow’s awkward interaction with their costar Elizabeth Perkins, who plays Big Josh’s love interest. “We were during a pre-rehearsal, I think in Penny’s office. … It was me talking to Elizabeth Perkins, and flirting. And I immediately get real quiet, and embarrassed. … And the first time that [Josh] realizes what’s going on, that’s a moment that was exactly like what I was going through in that room right there.”

Big returns to theaters July 15 and July 18 as part of Fathom Events’ 30th anniversary celebration.

Watch Tom Hanks update us on his presidential “campaign” with Dwayne Johnson:

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