This post contains spoilers for "Fast X"

"Fast X" had an impressive $320 million box office debut, suggesting audiences still can't get enough of the "Fast" franchise's high-octane action and outlandish set-pieces. Universal spent a mind-boggling $340 million on the tenth installment in the series. And while the whole premise of this franchise is to push the action further with each successive movie, there's more to its box office draw than physics-defying car chases and action spectacle.

Case in point: Jason Momoa. The "Aquaman" star plays the film's big bad, Dante, in Fast X, and his unhinged, chaotic performance is one of the main reasons the film is outrageously entertaining. And if you know anything about the behind-the-scenes woes the movie faced, specifically the abrupt departure of longtime "Fast and Furious" director Justin Lin, you won't be surprised to learn that Momoa actually improvised much of his ostentatious performance during shooting.

When director Louis Leterrier was brought in to replace Lin, he rewrote the "Fast X" script despite only having three days between being hired and calling action on-set. And based on the film's box office debut, the "Transporter" director certainly managed to pull everything together despite being rushed in at the last second. But much of his triumph is down to the cast, especially Momoa and his improv, which allowed him and Leterrier to find much of Dante's performance as they shot.

Momoa Vs Diesel

Only a bit of Jason Momoa's "Fast X" character came from the film's script. As Louis Leterrier put it in a Gizmodo interview:

"[Momoa] works, rewrites his dialogue, talks about character interaction, is so generous with the other actors and, you know, really willing to play. So his willingness to play worked really well with my envy to push it a little bit, to tweak the cursors and try stuff."

But the actor's improv went beyond trying different line readings and ad-libs. According to Momoa, who spoke to ScreenRant recently, there was a big fight planned between Dante and Vin Diesel's Dom, but the actor was keen to add a twist to the scene. Momoa reveled in having Dante enjoy taking a beating from Dom — the man partly responsible for the death of Dante's father back in "Fast Five."

As Momoa put it, "I think it's way more interesting, he gets the s*** kicked out of him, and he loves it. To get off on being beat up and just so he can get close to [Dom] because he's got the upper hand." And not only did Momoa play up his character's perverse enjoyment during this moment, he also came up with a memorable piece of improv that actually made it into the final cut. He added:

"I lost a molar. I never took my wisdom teeth out because I'm a wussy and I'm terrified of dentists. And so I cracked my molar. And so I have this gap here and I was like, 'This would be funny if you just beat the s*** out of me and I'll pull my tooth out and [say] 'dick or poopy' and just throw it at him […] And we just made all that up."

Momoa Was Clearly Having Fun

Dental improv wasn't the only spontaneity Jason Momoa brought to Dante. There's a particularly twisted nail polish scene that was also apparently made up on the spot and can be seen in the final cut of "Fast X." And that's just one of many examples, with Momoa clearly relishing the chance to finally play a villain in a big budget film.

But the fight between Dante and Dom is memorable because it calls to mind a scene between Heath Ledger's Joker and Christian Bale's Batman in "The Dark Knight." The interrogation scene, where Joker reveals he's kidnapped Harvey Dent and Rachel Dawes, sees Batman getting increasingly violent with his nemesis, delivering an intense beatdown only for Ledger's Joker to burst into laughter. It seems Momoa borrowed some of that energy for his face-off with Dom, and it works well here, even though it's not an entirely original choice. The tooth being knocked out is just the icing on the cake.

But perhaps even more impressive than the sheer amount of improv that made it into "Fast X" is the fact that Momoa's improvisation never managed to break Vin Diesel, who remained stoic in the face of his co-star's extemporaneous shenanigans. Which, considering the man's oddly serious perspective of the "Fast" films as more than an action franchise, and his grandiose comments about the films in general, isn't all that surprising. Let's hope Dante returns for the 11th film to balance out some of that self-seriousness again.

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The post Jason Momoa Improvised His Fake Tooth into a Fast X Fight Scene appeared first on /Film.