Twister.

It is a warm afternoon in the historic center of Rome, near Piazza Margana, and the film crew of "Duplicity," a romantic spy caper, is doing repeated takes of a fifteen-second shot. The movie's director, Tony Gilroy, who also wrote the screenplay, is at one end of an alley. The British actor Clive Owen stands near him, as does Julia Roberts. Nearby hover her makeup man and bodyguard, various assistant directors, gaffers, and carpenters, and members of the Italian crew. A black tarpaulin blocks the view of onlookers and the paparazzi. An assistant director calls for "last looks"--the final touchup by the makeup artists--and Roberts takes her mark, halfway up the street; Owen moves to the top of the alley. Gilroy calls "Action!" and is echoed by a "Movimento!" from the Italian assistant director who handles the extras.

Roberts begins walking down the street, and the cameraman, using a handheld steadicam, precedes her in a backward crab-walk. On cue, three children race up the alley past her, kicking a soccer ball. Roberts looks over her shoulder and continues until she is off camera. Moments later, Owen begins to walk fast; he breaks into a trot, runs past the children, decelerates, runs again. He is pursuing her. He runs until he runs out of street.

"Cut!" Gilroy cries. "That look is so strong," he says to Roberts. "That was great. That revealed a lot. Great." Roberts, who has already done several versions of this scene, is clearly exhausted. "My mojo's gone," she says. She also has the flu and an ear infection. The cast began filming at 4 A.M., outside the Pantheon. Gilroy assures her, "Even at quarter speed, you're still a thoroughbred." Roberts sits in her folding chair and removes her espadrilles; someone's hands take them from her. She sees the kids still playing with their soccer ball and adopts a mock-Chekhovian tone: "Oh, to be young and play in the heat and do it over and over and not complain about water or time or last looks." She turns to Gilroy: "O.K., I've come up with something that's really going to rock your world."

"I need an after-lunch pick-me-up," he says.

"Coming up."

"Let it rip!"

They shoot the scene once more. The children chase the soccer ball again; Roberts looks over her shoulder again, this time more subtly. The viewer is supposed to wonder, What, exactly, is she looking for?