Robert Downey Jr. hangs out with his ‘Oppenheimer’ costars Emily Blunt, Cillian Murphy and Matt Damon in New York City, with a surprise photobomb from John Krasinski.Photo:Robert Downey Jr./Instagram

Robert Downey Jr./Instagram
Robert Downey Jr.is all smiles with hisOppenheimercastmates!
The actor, 58, shared a pair of group photos on Instagram showing him hanging out with some of the stars of the highly anticipated biographical drama.
“Linking up with myOppenheimercastmates,” theIron Manstar captioned thepost.
The photos — one all-smiles and the other ironically serious — featured the N.Y.C. skyline in the background — as well as an unexpected appearance from Blunt’s husband,John Krasinski.
Downey acknowledged that one of the actors in the group photo was not like the others, joking, “Wait, is that a Krasinski photobomb or might there be a surprise cameo???”
Robert Downey Jr. poses with Emily Blunt, Cillian Murphy and Matt Damon in New York City.Robert Downey Jr./Instagram

Instead ofThe Officestar’s hilarious photobomb, however, it was Murphy’s grin that fans found to be most out of place in the group shot. Several commenters applauded Downey for capturing his costar — who is known for his serious roles inPeaky Blindersand28 Days Later— with a big smile on his face.
“Cillian looks too happy — this has to be photoshop,” one commenter joked, while influencer Brittany Broski wrote, “I am crying! How did you get Cillian to smile?”
Downey also highlighted one of his press tour outfits and showed some gratitude to N.Y.C. in a post on his Instagram Story.
“Most def not posing …” the star wrote alongside a photo of himself looking off-camera while dressed in a pale yellow suit, patterned shirt and gray combat boots. “Amazing buzz forOppenheimer. Thx NY! Paris here we come!”
“We’ll be back with a splash for our U.S. premiere,” he concluded the post.
Robert Downey Jr. shows off his outfit on his Instagram Story while on a press tour for ‘Oppenheimer.'.Robert Downey Jr./Instagram

Oppenheimer, which will debut in theaters on July 21, is based on the Pulitzer Prize–winning biographyAmerican Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer.
TheChristopher Nolan-directed film centers on J. Robert Oppenheimer (Murphy), who famously led the Manhattan Project — the effort to create an atomic bomb during World War II. Downey portrays Lewis Strauss, a former United States Atomic Energy Commission chairman and the main antagonist of the titular physicist.
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In addition to the stars featured in Downey’s N.Y.C. snapshot — sans Krasinski —Oppenheimer’s A-list cast boastsFlorence Pugh,Kenneth Branagh,David KrumholtzandJosh Peck.
source: people.com