Reese Witherspoon’s animal instincts

As far as tightly wound actresses go, Reese Witherspoon tops the list. She insists upon a strict sense of order in her life. Her production company is called Type A. And even when she appears to be having a spontaneous moment, lamenting that her well-orchestrated career built around an avoidance of bikinis has been breached by her current role as a leotard-clad circus performer, the line is a well-rehearsed quip that’s been repeated to scores of media outlets.

Which makes it all the more confounding that the 35-year-old actress would subject herself to the unpredictable behaviors of circus animals such as the almost nine-ton elephant Tai and a slew of trick horses when she shot the adaptation of the Depression-era romance

Water for Elephants

, in theaters Friday.“I have anxiety. I get nervous, and I shake,” Witherspoon tells the Los Angeles Times. The night before shooting with the elephant, “I didn’t sleep, and I literally shook and shook and shook,” she says, feigning relaxation in a hotel room chair, still perfectly coiffed in a gray dress and three-inch heels after a long day of enchanting the international press corps. “But the performances with the elephant were really magical for me. Against my better instincts I decided to ride the elephant with no harness, with no safety equipment. It was pretty great.” The native Southerner seems to be doing a lot of leaping without a protective net. After ending her eight-year marriage to actor

Ryan Phillippe

in 2007, she recently tied the knot with

Jim Toth

, an agent at CAA where Witherspoon is also repped. She’s moved easily between big studio projects and smaller films,but

Water for Elephants

is something of a hybrid. It’s a roughly $40-million adult drama but it’s based on a bestselling novel by Sara Gruen and costars one of the hottest properties in town in Pattinson.In the film, Marlena is trapped in an abusive marriage with the volatile ringmaster August (

Christoph Waltz

). When she meets the younger, veterinarian Jacob Jankowski (Pattinson), she discovers there’s a lot more living to be done beyond the big top.“She’s got her life wound so tightly and controlled down to every detail,” Witherspoon says of Marlena, but you get the sense she’s really speaking autobiographically. “You know whenever you feel terribly out of control, you try to control everything and keep it very small. Then in comes this Jacob character: idealistic, young and hopeful. … For me, this movie is about optimism, that second chances are possible. And to be fearless in your decision-making.”