Gwyneth Paltrow, Brad Falchuk Debut Romance at Robert Downey Jr.’s Star-Studded 50th Birthday Party

Gwyneth Paltrow and Brad Falchuk
Months after Us Weekly broke the news that they were dating, Gwyneth Paltrow and Brad Falchuk stepped out together at Robert Downey Jr.'s star-studded 50th birthday party  Theo Wargo/Getty Images; Frazer Harrison/Getty Images

No longer undercover lovers! Seven-and-a-half months after Us Weekly first broke the news of their romance, Gwyneth Paltrow and Brad Falchuk made their big debut as a couple at Robert Downey Jr.'s star-studded 50th birthday party on Saturday, April 4. 

The Mortdecai actress, 42, and the Glee producer, 44, were among a group of about 250 people who gathered to fete the Avengers: Age of Ultron actor at a lavish bash that even Tony Stark would envy. (Paltrow played Downey Jr.'s on-screen love interest Pepper Potts in all three Iron Man movies, as well as in the first Avengers film.)

The couple arrived at Santa Monica Airport's Barker Hangar just a few minutes before the guest of honor, a source tells Us Weekly. As they walked into the venue — where different rooms had been set up to represent various periods of Downey Jr.'s life — Falchuk put his hand on Paltrow's lower back, guiding her through the crowd.

And what a crowd it was. Celebs flocked in droves to celebrate the Sherlock Holmes star's half-century birthday on Saturday night.

Robert Downey Jr. Birthday Party
Robert Downey Jr. Gabriel Grams/WireImage

Among the revelers were Orlando BloomJason BatemanDustin HoffmanJustin Theroux and Jennifer Aniston,Tobey Maguire and Jen MeyerEdward NortonReese WitherspoonJack OsbourneKatie Holmes, and Gwen Stefani and Gavin Rossdale. Fellow Avengers stars Samuel L. Jackson and Jeremy Renner were also on the guest list.

A few minutes after 6:30, the birthday boy himself arrived with wife Susan. As he entered the party — through a tunnel of smoke, natch — speakers blared "It's My Party."

There was live music, too — from none other than Steely Dan and Duran Duran, the latter of which played a 45-minute set including hits like "Come Undone," "Rio," and "Ordinary World." Toward the end of the bash, everyone joined together in singing "Happy Birthday" to Downey Jr.

The party wound down around midnight, but Paltrow and Falchuk snuck out early, a source tells Us.

As previously reported, the two met when the actress guest-starred as Holly Holiday on Glee back in 2010. "Things started off professionally," an insider told Us last fall, but their bond turned romantic after Paltrow split from husband Chris Martin in March 2014.

Martin, for his part, moved on with Jennifer Lawrence. He and the Hunger Games actress spent a romantic weekend together in New York on April 4 and 5.

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