Oppenheimer might be based on a true story, but fans of history noticed something not so historically accurate.
The scene in question takes place in 1945, after the bombings of Hiroshima and Nagasaki. J Robert Oppenheimer, played by Irish actor Cillian Murphy, is about to give a speech to a cheering, patriotic crowd of Americans. The crowd is waving American flags, and that's where the inaccuracy lies.
One moviegoer took to Twitter to write that the film "was good and all, but I'll be that guy and complain they used 50-star flags in a scene set in 1945".
In 1945, there were only 48 stars on the American flag, as the stars represented how many states the United States had. Alaska and Hawaii weren't considered states during the time, however, the flags had all the current 50 stars on them. Alaska and Hawaii didn't become states until 1959.
It seemed to be a one-scene-goof, as other scenes set in the 1940s had the correct flags of the time. However some fans think this might have been a deliberate choice by director, Christopher Nolan.
We live in city where Peaky Blinders is filmed - it’s worse than the show"Personally, I think it was done intentionally because coloured scenes were from Oppenheimer's perspective which is his present day's memory that was after the 50-star flag was established," one fan wrote.
Another fan was left fuming as they said: "Totally ruined the film for me."
Oppenheimer takes place in three different time periods in Oppenheimer's life, first his early life and the creation of the atomic bomb, then his 1954 security hearings, and finally with Lewis Strauss, played by Robert Downey Jr., being confirmed to the United States Senate in 1959.
The release of Oppenheimer in theatres coincided with the release of Greta Gerwig's Barbie, creating what fans have dubbed "Barbenheimer." Fans flocked to the cinema to attend a double feature of the films, creating a discussion online about what order the two very different films should be seen in.
Once the weekend arrived, fans dressed up for their cinema trip and many memes popped up on the internet. Both movies did well at the box office, so far Barbie has made $382.3million (£296million) worldwide and Oppenheimer grossed over $180.4million (£140million).
Oppenheimer also stars Florence Pugh, Emily Blunt, Matt Damon, and more A-list blockbuster stars.