Casting is a difficult and underrated process. Many moviegoers don't recognize or appreciate good casting. But if it seems like an actor was "born to play the role," chances are it was undertaken by an exceptionally gifted casting director. Contrasting this, many people do recognize bad casting, and social media s aren't afraid of voicing their displeasure when it comes to a poorly cast character (especially if they're from an established IP).

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Casting can make or break a movie, just as a particular actor can make or break a character. These movies are perfect examples of wonderfully cast films.

Robert Downey Jr. As Tony Stark

Avengers Endgame Tony Stark Talks to Captain America

Marvel knows how to make movies, and that includes the casting process. As Reddit  jigokusabre states, "Robert Downey, Jr. is the perfect Tony Stark." It is indeed one of the most perfect casting choices in recent memory.

Downey perfectly conveys Stark's sarcastic sense of humor and ive personality, but he also finds the humanity and vulnerability underneath. Even among the perfectly cast MCU, the casting of Downey was a piece of genius inspiration - and even Stan Lee backed it.

Alan Rickman As Severus Snape

Snape holding his collar in Harry Potter

Severus Snape is one of the best characters in Harry Potter and the Sorcerer's Stone - and the entire series for that matter. Reddit  Shadrimoose thinks that Alan Rickman was perfectly cast as Snape, writing, "Alan Rickman as Severus Snape. The first time I saw him on the big screen it just clicked."

The entire Harry Potter franchise was exceptionally cast, but Rickman is indeed perfect as Snape. Even when re-reading the books, it's impossible not to picture Rickman as the quiet and pensive potions teacher.

J.K. Simmons As J. Jonah Jameson

J. Jonah Jameson smoking a cigar in his office in Spider-Man

Reddit Spider-Man. Could not have done a better job with that role: the look, the voice, and the expressions." It is indeed an inspired bit of casting.

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So inspired, in fact, that Simmons is the first actor to portray the same character in two Marvel universes (having reprised his Tobey Maguire role as Jameson for the Tom Holland films). He's so perfect that the producers just couldn't let him go.

Heath Ledger As The Joker

Joker showing a bomb inside his jacket in The Dark Knight.

According to Rotten Tomatoes, the best Batman movie to feature The Joker. It's no surprise, given the incredible performance from Heath Ledger. This Reddit  thinks "Heath Ledger as the Joker" is one of the most inspired bits of casting in movie history, and they certainly have a point.

The casting of Ledger may have raised a few eyebrows at first, but he proved impeccable in the role. To this day, people are still imitating his lip smacks and unique way of talking.

Anthony Hopkins As Hannibal Lecter

Anthony Hopkins as Hannibal Lecter staring into the camera in The Silence of the Lambs

Mads Mikkelsen is fantastic as the legendary cannibal, but there's simply no beating Anthony Hopkins. Reddit  The Silence of the Lambs holds up remarkably well today, and Hopkins's performance as Lecter is a big reason for it.

Hopkins not only turned the character of Hannibal Lecter into a cinematic icon and household name, but he helped The Silence of the Lambs sweep the Big Five Oscars - a feat that hasn't been attained since.

Johnny Depp As Captain Jack Sparrow

Captain Jack Sparrow standing at the mast of his ship in Pirates of the Caribbean

The Pirates of the Caribbean was a surprise hit for Disney. No one predicted just how massive the movie would become, and its popularity was largely due to the legendary performance of Johnny Depp. Reddit  Cappelitoo calls "Johnny Depp as Captain Jack Sparrow" a perfect casting choice, and everyone will probably agree.

Depp created the most iconic cinematic pirate of our time, and the stellar performance helped relaunch his then-fading career. This is one of those characters that will never be forgotten.

Tom Hanks As Forrest Gump

Tom Hanks sitting on a bench in Forrest Gump

Forrest Gump is undeniably one of Tom Hanks's most likable characters, and he is rightfully regarded as a cinematic icon. A deleted Reddit calls "Tom Hanks Forrest Gump" a perfect casting choice, and if history is any indication, they are absolutely correct.

Hanks's performance was a major reason for Forrest Gump's success, and many aspects of his character (especially the voice) have been widely parodied and referenced for generations. It's one of those perfect marriages between character and actor, and it's impossible to envision anyone else in the role.

James Earl Jones As Darth Vader

Darth Vader reaching his hand out in Star Wars

Reddit  Star Wars trilogy, Darth Vader was physically played by David Prowse while James Earl Jones provided his voice. And while Prowse certainly did a good job, the role of Darth Vader has forever been linked to Jones.

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His signature deep voice was absolutely perfect for the role, providing Darth Vader with the necessary menace. His voice is unmistakable, and it has been firmly burned into the memories of millions.

Viggo Mortensen As Aragorn

aragorn talking to haleth in The Lord of the Rings

Reddit  The Lord of the Rings, but his poetic and quiet personality was a perfect match for the character of Aragorn.

The casting is especially genius because Mortensen was actually a last minute replacement for the character, as original actor Stuart Townsend was deemed too young for the role. Not bad for such short notice.

Matthew Lillard As Shaggy

Shaggy and Scooby looking scared in live action

A Scream and She's All That.

It was perhaps the most surprisingly great casting choice of the 2000s, as Lillard became Shaggy. Like J.K. Simmons as J. Jonah Jameson, Matthew Lillard eventually became the de facto Shaggy, portraying him in all future Scooby-Doo movies and TV specials. With Lillard, Mary Vernieu found the perfect Shaggy.

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