Steven Spielberg is a legendary filmmaker, a box-office behemoth and an Oscar winner, but there's one thing he can't do very well: imitate a Tyrannosaurus rex.

Twenty-one years since the original "Jurassic Park," the franchise is still as buzzy as ever, with a new installment slated for summer 2015. But working on the 1993 movie that started it all was "just like working on an independent film," star Laura Dern told HuffPost Live's Ricky Camilleri on Tuesday.

Dern called "Jurassic Park" "the first CGI movie" and remembered the on-set comedy of figuring out how to act alongside gigantic dinosaurs that weren't really there:

I remember we were all standing in a row, and this crane of, like, chewed up metal comes up, and we're supposed to realize what the T-rex can do and all have this look to the side when we hear a sound. And we did a take and then we cut and Steven's like, "You guys were all looking different directions." We said, "Steven, we're supposed to respond to the sound and there's nothing there. We don't know when we're supposed to respond, so we're responding at different times." He goes, "Oh, oh, okay, I got this." Rolling and action! And we're all there looking, and the camera pushes in, and then Steven, through a megaphone, goes, "RAWR! RAWR!" And all of us looked at each other, and I remember Richard Attenborough going, "Oh, Steven, um, this is troubling."

Dern visited HuffPost Live along with author Cheryl Strayed to discuss the big-screen adaptation of Strayed's book, "Wild," which hits theaters Dec. 5.

Watch Dern's hilarious recollections from the "Jurassic Park" set in the video (above), and catch the full HuffPost Live conversation with Dern and Strayed.

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