Leonardo DiCapriowas a big star in the ’90s, appearing inWhat’s Eating Gilbert Grape,Romeo + Juliet, and, of course,Titanic. His fame has only risen since then, appearing in countless blockbusters across two decades. Around the same time, filmmakerMichael Mannwas near the height of his career and dreamed of making aJames Deanbiopic, and the director thought he had found the perfect actor to play him.

Mann recently toldDeadlinehe scrapped a ‘brilliant screenplay’ about the late actor due to DiCaprio looking too young to play the part. Instead, the director would go on to filmHeat, a crime/drama revolving around professional thieves, starring Al Pacino, Robert De Niro, Val Kilmer, and Jon Voight. The movie was received well by critics and fans and has since become a classic heist film. However, despiteHeatbeing one of the most successful movies of Mann’s career, he still reminisces about what could’ve been with Leonardo DiCaprio.

Leonardo DiCaprio: Jack

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He tells Deadline it would be difficult to find someone who could play theRebel Without a Causeactor, but ‘I found a chap who could play James Dean.’

“It was a brilliant screenplay. And then it’s who the hell could play James Dean? And I found a chap who could play James Dean, but he was too young. It was Leo. We did a test screen that’s quite amazing. I think he must’ve been 19 at the time. And from one angle, he totally had it with him. I mean, it’s brilliance.”

TheThiefdirector believes the reading occurred sometime betweenGrowing Pains(1992) andWhat’s EatingGilbert Grape(1993) before the star would reach worldwide fame withTitanic. If things had taken a different turn, Leonardo DiCaprio might have been known for his breakout role in the James Dean biopic.

Mann Say’s DiCaprio’s Performance Was All in the Facial Expressions

Michael Mann was impressed with DiCaprio’s short portrayal of Dean and claimed his excellence had everything to do with the facial expressions. The director says DiCaprio could instantly change his emotions and expressions, turning into the late actor.

“He would turn his face in one direction and we see a vision of James Dean, and then he’d turn his face another direction and it’s no, that’s a young kid. I found the absolutely perfect act of the play, in about three years from that. He respectfully undid the James Dean bio for me.”

Neither Mann nor DiCaprio can be mad at the way things turned out, with the filmmaker going on to direct several successful films aside from his masterpiece,Heat. DiCaprio would garner seven Oscar nominations so far through his career, with one win for Best Actor in the 2015 filmThe Revenant.

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Mann recently released a prequel/sequel novel toHeat, titledHeat 2,which the filmmaker is then adapting into a feature film. Unfortunately, he’s confirmed neither Robert de Niro nor Al Pacino would be able to reprise their roles as their younger selves. However, this gives a chance for the director to cast his long-awaited partner, Leonardo DiCaprio.