Katie Holmes steps out in New York City, smiling but minus wedding ring

Katie Holmes has stepped out in public for the first time in public since announcing she had filed for divorce from Tom Cruise — reportedly smiling and without her Cartier diamond-studded wedding ring. 

Holmes, 33, emerged in New York City late Monday to make a guest-judge appearance on "Project Runway: All Stars" at Parsons The New School of Design in Manhattan, according to the New York Daily News. 

The News wrote that Holmes, wearing a long-sleeved, navy shirt dress, was surrounded by a new group of security guards, having fired the ones hired by Cruise.

According to London's Daily Mirror, she has also reportedly returned to pre-marriage publicist Leslie Sloane at BWR.

The paper cited a statement as saying: "Actress Katie Holmes has left her publicist at Slate PR and has signed with BWR Public Relations. Following the announcement of her divorce from Tom Cruise, she is now represented by Leslie Sloane in the New York office and Nanci Ryder in Los Angeles. Katie is set to star alongside Chace Crawford in the upcoming film Responsible Adults which starts filming later this year."

Us Weekly, meanwhile, has written wrote that Holmes' divorce filing June 29 was a year in the making.

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According to TMZ, Holmes was convinced Cruise, 50, planned to send their daughter Suri, 6, to Scientology "boot camp" — a group called Sea Organization.

The split left Cruise "devastated and heartbroken," a source told People. "He had no idea this was coming."

Despite Holmes' smiles Monday, a source told Us Weekly: "She looked really sad and was looking at the ground the whole time."

Holmes was planning to live with Suri in New York, where she had rented a $12,000-per-month apartment. She had reportedly been moving into the apartment over the past couple of weeks.

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