Lord Voldemort is not only one of the most important characters from the Harry Potter series, but he has become a cultural icon: equally famous as the Boy Who Lived he spends years antagonizing, he is a linchpin of villainy, and along with Star Wars' Darth Vader, the go-to "bad-guy" to describe those in power causing harm to everyday folk.

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Voldemort was in his seventies by the end of the Harry Potter series. The eight films take place over seven years during Harry's time at Hogwarts School of Witchcraft and Wizardry, and while we wouldn't expect to see much physical change in an individual in that age bracket, Voldemort, or as he was previously known, Tom Riddle, is portrayed by six different actors throughout the series. For the most part, the Voldemort in the series timeline is played by one actor, but we are treated to many flashbacks and memory sequences, allowing both Harry and the audience a glimpse of what Voldemort was like as a young man, before his disfigurement through dark magic.

6 Voldemort Was First Introduced As Less Than Human

The audience and Harry both learn of Voldemort in the first film of the franchise, Harry Potter and the Philosopher's Stone (2001). Hagrid explains to Harry the story of his tragic past, and through flashback we see a hooded Voldemort, played by Richard Bremmer attack and kill Harry's parents before his killing curse aimed at the baby Harry rebounds and lands on Voldemort himself. Later in the film, Professor Quirrell unwraps his turban from his head and reveals a weakened Voldemort is feeding off him and living on the back of his head. Both Quirrell and Voldemort were played by 33-year-old Ian Hurt, and it wouldn't be until the following year saw the release of the second film, Harry Potter and the Chamber of Secrets, that we would get our first glimpse of a Voldemort in his youth.

5 Christian Coulson Played A Young Tom Riddle

Only a year after defeating the Voldemort housed in the back of Professor Quirrell's head, Harry Potter meets another variation of the Dark Lord. Tom Riddle was a 16-year-old high school student at Hogwarts when he preserved his memory in a diary, ready to be utilized by the heir of Slytherin to open the Chamber of Secrets once more. British actor Christian Coulson was cast as Tom Riddle, the first time we are introduced to a young Voldemort. Coulson himself was 24 when he played the role, but his boyish looks, sharp jawline, and thick dark curls worked perfectly in his portrayal of the handsomely charming 16-year-old villain.

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4 Ralph Fiennes Famously Played Adult Voldemort

The next time we see the character wouldn't be until 2005 when Ralph Fiennes took on the role in Harry Potter and the Goblet of Fire, the fourth film in the series. Fiennes, who was initially reluctant to take on the role, would famously continue to play the adult Voldemort in the fifth, seventh, and eighth outings as well. He was only missing from the sixth film, Harry Potter and the Half-Blood Prince, as the storyline for that film dove into Voldemort's past, introducing us to the story of Voldemort's childhood, and providing the chance for another young actor to take on the role.

3 Hero Fiennes Tiffin Played A Pre-Teen Voldemort

Unlike Coulson, Hero Fiennes Tiffin was the same age in real life as the character he was playing - 11-years-old. Through a memory of Dumbledore, we saw Hero Fiennes Tiffin, the nephew of adult Voldemort actor Ralph Fiennes, introduce the world to a pre-teenage, orphaned Tom Riddle, ignorant of his wizarding blood and confused by his ability to whisper with snakes and make bad things happen to people who are mean to him. But an 11-year-old Voldemort was just the beginning for the film. We are also introduced to another memory, of 16-year-old Tom Riddle again, this time set in the year leading up to him opening the Chamber of Secrets. And how lucky for the production that they already had an actor cast as 16-year-old Tom Riddle!

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2 The Real Reason So Many Actors Played Young Voldemort

Not so lucky in the end. As Harry Potter and the Half-Blood Prince was going into production five years after Chamber of Secrets, Coulson was now 29 years old, and unfortunately no longer believable as a 16-year-old school student. Hero Fiennes Tiffin was evidently too young to play the older Tom Riddle as well. At 11-years-old, it was not an option to age him up either. So it was that Warner Bros. had to cast another young actor to take on the role of You-Know-Who as he truly began to lean into his dark nature in his quest for immortality.

1 Frank Dillane Played A Teenage Voldemort

Frank Dillane would be the final actor cast as He-Who-Must-Not-Be-Named throughout the eight-film series. Dillane, the son of Game of Thrones actor Stephen Dillane, attended an open casting call and went through seven auditions before landing the part. He appears in memories of Professor Slughorn, conveying, as the New York Times put it, "the seductiveness of evil with small, silky smiles he bestows like dangerous gifts on Jim Broadbent’s Horace Slughorn."

Next: Every Actor Who Has Played Voldemort, From Ralph Fiennes To Eddie Izzard