The legend  Robert Downey Jr. is one of the biggest actors on the planet at this point, and his time in the MCU helped make him a legend. The potential was always there with Downey, but it took him some time to figure it all out. Once he did, there was simply no stopping him from reaching the top.

Despite his success, Downey has had some missteps, including a missed opportunity to star in the film Gravity. It seems that any studio parting ways with Downey for a project would be a mistake, but the gamble paid off here.

So, why did George Clooney replace Robert Downey Jr. in Gravity? Let’s take a look and see.

Downey Was Going To Star In Gravity With Sandra Bullock

Studios looking to cast big-budget projects will normally look to bankable stars that have a proven track record at the box office. After all, there projects can cost hundreds of millions of dollars, and the last thing that investors want is to sink their money into something that has a low rate of return. So, it makes sense that the folks making Gravity cast Robert Downey Jr. as their A-list lead.

By that point, Downey had completely reinvigorated his career as the face of the MCU. While he had his ups and downs in the past, his time as Tony Stark proved to be just what the doctor ordered for his career. With everything under control and trending upward, Downey was paired with Sandra Bullock in the film Gravity, and the movie had massive potential.

Bullock, much like Downey, was a proven star that had already done huge things as a lead performer. Sometimes, the stars align just right, and movie fans were excited to see what a pairing of Downey and Bullock would look like on the big screen. To make things even sweeter, the film was going to be using groundbreaking technology to bring the script to life.

However, things on paper can often look better than they do in reality, and once production got underway for Gravity, it quickly became clear that there was an issue that would prevent this movie from becoming a blockbuster smash at the box office.

Related: Is Robert Downey Jr.’s Son, Indio Falconer Following In His Dad’s Footsteps?

His Acting Style Was A Bad Fit

Finding the right person for the right role is a tricky part of making movies, and the folks making Gravity faced this problem after production began. Despite being a terrific actor, Robert Downey Jr. was not a good fit for the technology that the team was using to bring the film to life.

When speaking about what took place, director Alfonso Cuaron would say, “It became very clear that, as we started to nail the technology, or narrow the technology, that was going to be a big obstacle for his performance. I think Robert is fantastic if you give him the freedom to completely breathe and improvise and change stuff. [But] we tried one of these technologies and it was not compatible.”

“And, after that, we [had a] week that we pretended as if nothing was happening and then we talked and said, ‘This is not going to work. This is tough’,” he continued.

It’s hard to imagine someone like Robert Downey Jr. getting replaced for a role, but the money that went into making the movie needed to be recouped, and there was simply no way that having the wrong lead performer was the right route to take.

Related: Here’s Why Robert Downey Jr. Relates To Tony Stark

Downey Heads Out, Clooney Steps In

With Robert Downey Jr. out of the picture, the studio needed to quickly find the right man for the job. That man wound up being George Clooney, who stepped into the role and did an exceptional job in the movie. Sure, Bullock stole the show, but Clooney did a great job in his own right.

Released back in 2013, Gravity would go on to gross over $723 million at the global box office, making it a huge success. The decision to swap actors worked out brilliantly, and the studio had to be happy with the way that things played out.

At the Academy Awards, Gravity would land some impressive hardware, including Best Director, Best Cinematography, Best Original Score, and more, according to IMDb. Sandra Bullock was nominated for Best Actress that same evening, and the film itself was nominated for Best Picture. All of the hard work paid off, and Gravity has since gone down as a huge cinematic achievement.

Related: Here’s How Robert Downey Jr.’s Costars Felt About Working Onscreen With Him

Robert Downey Jr. may have been the original man for the job, but he was not the right man for the job.

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