All summer long Jennifer Aniston and Vince Vaughn have worked side by side in Chicago, shooting scenes of warm intimacy for their upcoming romantic comedy The Break-Up. And so it was a familiar sight when the two were spotted together—her head resting on his shoulder, his arm draped across the back of her neck—in the wee hours of Aug. 15 at her hotel. Except that this time, there were no cameras, no extras, just a tired duo sharing a quiet moment. "They looked very cozy and familiar," an observer says of the pair, who were joined by Aniston's bodyguard as they strolled to the elevators.

Throughout the two-month Break-Up shoot, Aniston, 36, and Vaughn, 35, have consistently denied rumors of a romance, even as they have shown up together—always as part of a group—at various Chicago hot spots. (As for photos of the two kissing that ran in Britain's Daily Mirror, the pictures were taken during a publicity shoot for The Break-Up.) "She is having fun in Chicago with Vince and the whole cast and crew," says Aniston's rep Stephen Huvane. "Nothing romantic." Aniston herself said as much in her recent Vanity Fair interview, telling the magazine, "I adore Vince Vaughn, but I'm not going out with Vince Vaughn.... I like a lot of people, but I'm sooo not 'in like' with anybody." Likewise, Vaughn downplayed the rumors to Katie Couric last month, noting, "[Jen's] been great, and we've been having a great time shooting the movie. But that's really been the extent of it."

Moving on since her split with Brad Pitt in January, Aniston has relied heavily on new friends, like Vaughn; old friends, like hairstylist Chris McMillan and Courteney Cox Arquette; her constant companion, a corgi-terrier mix named Norman; and work. She has shot four films back-to-back but rarely been sighted off-set. In recent weeks, however, she seems to be emerging from her post-breakup shell and diving into the Chicago scene. While shooting The Break-Up, the actress has been breezing through the Windy City, from taking in the skyline from the John Hancock Observatory (with Brad's mom!) to eating out at restaurants Coco Pazzo and RL. "She's doing great," says a source close to the actress. "She's moving on with her life." (On Aug. 9 Aniston and Pitt filed papers showing that they have agreed to permit a retired judge to handle their divorce privately, a move that should make the proceedings as discreet as possible.)

How Vaughn fits into her life remains the subject of much speculation. Still, there's no question that Aniston and Vaughn, who play a divorced couple forced to live together in The Break-Up, have clicked. With shooting set to wrap soon, Aniston treated Vaughn, along with the rest of the cast and crew, to a sunset party on Aug. 14 aboard the 200-ft. yacht The Odyssey. Two nights earlier the pair turned up in a group of 15 at Chicago's Japonais restaurant-lounge. At one point the group was dancing together, says an observer, with Aniston and Vaughn getting especially close: "It was playful and sexy—they looked like they were really enjoying each other." And Aniston, for one, looked like a woman on the upswing. "You go, girl!" shouted one female fan. "Stress must agree with you—you look amazing!"

Michelle Tauber and Samantha Miller; Barbara Sandler; Kelly Williams in Chicago; Julie Jordan in Los Angeles

  • Contributors:
  • Barbara Sandler,
  • Kelly Williams,
  • Julie Jordan.