Biopics are very unique films, as they give audiences a chance to connect with an iconic figure in a way that they might not have before. Performers and bands like Queen and Ray Charles have been given the biopic treatment, and their amazing movies helped their legacies grow even more after becoming hit films.

During the 2000s, Walk the Line, a biopic about Johnny Cash, became a huge hit, and Joaquin Phoenix and Reese Witherspoon were excellent in the film. Working together, however, was not always easy, especially when learning to sing and play like Johnny and June Carter Cash.

Let's take a look back at how the actors prepared for Walk the Line and how they learned to work alongside one another to help make the film a hit.

'Walk The Line' Was A Hit Film

Back in 2005, Walk the Line made its way into theaters with a ton of hype behind it. The film was set to be a biopic about the notorious Johnny Cash, and director James Mangold had himself a star-studded cast who were ready to drop jaws with what they were doing in front of the cameras and in the recording studio.

Starring Joaquin Phoenix and Reese Witherspoon, Walk the Line was a commercial success that grossed over $180 million at the box office. The film received an exceptional amount of critical acclaim, as did the lead performers who each found themselves up for an Oscar. Witherspoon would take home Best Actress that year, which furthered her legacy in Hollywood.

Overall, the movie was quite an achievement, and even now, people love popping it on and watching it all over again. It's a good thing that the film was a hit because there was a ton of work that went into making it happen.

Related: Before Playing The Joker, Joaquin Phoenix Passed On Playing Another DC Villain

Phoenix And Witherspoon Had To Take Singing Lessons

Fans always get to see the final product when enjoying a movie, but what they don't see are the months and sometimes years of preparation that go into bringing a movie to life. Everyone involved puts in the time and effort, and for the actors, they really need to bring their A-game, especially in a biopic.

For Reese Witherspoon and Joaquin Phoenix, transforming into an iconic country music duo required a ton of preparation, including taking singing lessons so that they could get close to sounding like the real deal. It's rare that an actor nails the singing of an icon, but these two did a heck of a job in Walk the Line.

According to Country Rebel, "Phoenix and Witherspoon did all their own singing in the film. They even learned how to play the instruments their characters played. Phoenix learned to play the guitar in the unique Cash style and Witherspoon learned how to play the auto harp."

Talk about going the extra mile!

All of this is great, but the truth is that the work that went into making movie magic was intense. It even led to some clashing between the film's stars.

Related: Joaquin Phoenix Lost Too Much Weight For 'Joker' And It Caused Production Problems

It Wasn't Easy Working Together

According to Witherspoon, "It took us about three months to trust each other because we didn't know each other at all in the beginning and we couldn't even look at each other when we had to sing to each other because it was so embarrassing. I'd sing too loud and he'd say, 'It's driving me crazy, she's singing too loud. Does she have to sing so loud?' I said, 'I'm just trying here!' It took about three months before we responded to each other's work and saw improvement. It took a long time before we really felt comfortable with each other."

There is already a lot of pressure when it comes to making a movie, but taking on iconic country music figures adds a new level to it all. It sure sounds like it wasn't easy to prepare for this film, and we can only imagine what it was like having to go through these rehearsals with a total stranger.

As tense as things were between them while gearing up to film, they eventually settled into a groove together.

"'Don't beat yourself up, you're doing a really good job.' We really leaned on each other and became close in that way," said Witherspoon.

Related: Fans Call Ashton Kutcher & Reese Witherspoon's New Netflix Rom-Com A ‘The Holiday’ Knock-Off

At the end of the day, all of the hard work that went into making Walk the Line paid off, as the film was a hit that earned its stars immense amounts of critical acclaim.

Next: Reese Witherspoon Fans Think She Shaded Ex Ryan Phillippe As She Talks Motherhood