The effortlessly stylish former Dawson's Creek star was snapped giving a smile to photographers as she prepared to film the New York-based drama on Tuesday (1 April).
For Katie, 35, it will mark her return to the small screen for the first time since playing Joey Potter on Dawson's Creek.
It's definitely a very different role, though!
Dangerous Liaisons is about two New York socialities "equally skilled in the art of manipulation, living by their own amoral codes." Yikes.
Katie seems to be having a ball filming it, tweeting yesterday: "Having great time working on dangerous liaisons pilot (sic)."
The brunette lives in New York with daughter Suri, seven, whose dad is Hollywood actor Tom Cruise. Katie and Tom divorced in 2012 after five years of marriage.
Speaking to ELLE magazine recently, Katie said of motherhood: "I think the basics are very important: the number one thing is making sure my child feels loved. And good about herself. And that what she does and who she is, is special and important, and should be celebrated.
"And my mum always said, 'No one loves you like your mother.'"
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