Katie Holmes Tapes Project Runway 4 Days Post-Split

Katie Holmes visits Chelsea Piers on June 22, 2012 in New York City. James Devaney/WireImage.com

Although she filed papers to divorce Tom Cruise last Thursday, Katie Holmes didn't jet to a tropical island to get away from it all.

Instead, the 33-year-old Jack and Jill actress is getting back to work. The star and designer was spotted Monday shooting another guest-judge stint on Project Runway, a source reveals to Us Weekly.

Keeping an already-confirmed commitment, Holmes showed up at NYC's Parsons School of Design in downtown Manhattan on Monday. Previous guest judges on the hit (which debuted on Bravo but subsequently moved to Lifetime) have included Victoria Beckham, Jessica Simpson, Kim Kardashian, Miranda Kerr, Zoe Saldana and Olivia Palermo.

As Us previously reported, Holmes prepped for her surprise filing from Cruise, 49, by secretly renting a $12,000-a-month apartment of her own in NYC, quietly moving in to the residence in the past couple weeks.

She and daughter Suri, 6, were spotted out and about in NYC on June 24. The smiling mommy-daughter duo sported coordinating black-and-white ensembles and stopped at their favorite spots Serendipity 3 and the American Girl Store.

"She's been miserable for a long time, but the last couple of weeks, she's been happy — like she's been set free," one source tells Us.

Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!

Want stories like these delivered straight to your phone? Download the Us Weekly iPhone app now!