John Krasinski “Photo Bombs” Robert Downey Jr.’s “Oppenheimer” Cast Photo

Robert Downey Jr.‘s attempt to snap the perfect “Oppenheimer” cast photo was hilariously thwarted by John Krasinski. The “Iron Man” actor posted two photos featuring his “Oppenheimer” costars on Instagram on July 9, but one of them featured an interloper in the form of Emily Blunt‘s husband. “Linking up with my Oppenheimer cast mates…wait, is that a Krasinski photo bomb or might there be a surprise cameo???” Downey captioned his post.

When it comes to movies from director Christopher Nolan, it’s always best to expect the unexpected, but it seems unlikely Krasinski will pop up in the film. Instead, he was most likely on hand to support Blunt, who plays a key role in the movie about J. Robert Oppenheimer, the man who led the Manhattan Project. Blunt joined Downey in the photos, alongside their fellow castmates Matt Damon and Cillian Murphy.

Krasinski’s scene-stealing moment isn’t the only thing that caught the attention of Downey’s Instagram followers. Many of Murphy’s fans commented on the post to share how surprised they were to see the actor smiling. Over the years, Murphy has made a name for himself playing serious roles on TV (“Peaky Blinders”) and in film (“Oppenheimer,” “28 Days Later”). As a result, he rarely ever gets to break out a genuine grin on screen.

“Cillian wasn’t just smiling, he’s wide smiling. this doesn’t feel right,” one commenter wrote. Another person wrote, “Never seen cillian this happy,” while YouTuber Brittany Broski added, “I am crying! How did you get Cillian to smile!”

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The answer to that question seems pretty simple: it was clearly due to Krasinski putting his years of pulling faces on “The Office” to good use in the background. Check out both cast photos below to see Krasinski’s expert photo-bombing skills in action, as well as a rare smile from Murphy.