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Puberty has been very, very good to Neville Longbottom -- but he's not the only one.

Matthew Lewis might continue to make us swoon over his journey from adorable round-faced Neville to -- well, this:

But there's another actor from "Harry Potter" that underwent a similarly incredible transformation -- Harry Melling, who played Harry's mean cousin Dudley Dursley.

For comparison, this is what he looked like at the premiere for "Harry Potter and the Prisoner Of Azkaban" in 2004:

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And here's what he looked like in 2013:

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Melling began losing weight after he turned 15, He told the Daily Mail, and by the time "Harry Potter and the Deathly Hallows Part 1" started filming he was almost unrecognizable -- so much so that he had to wear a fat suit for his scenes in the movie.

Since then he's been keeping just as busy as his former co-stars -- but rather than speak at the U.N. or pose for half-nude photoshoots, he's opted to spend his time honing his craft on the stage. He's starred in two different plays at the prestigious National Theater in London, (including "Mother Courage and Her Children" with his on-screen mother, Fiona Shaw), and last year he wrote and starred in his own one-man play called "Peddling," which he performed off-Broadway in New York before bringing it back to London this March. He also recently just ended a tour around the U.K. with "The Angry Brigade," a show about British anarchists.

Here he is hanging out in NYC in 2014, in case you don't believe us that he's totally changed:

Oh, and in case you were wondering, he doesn't miss being part of a giant movie franchise -- mostly because he doesn't think people remember his role in it for the right reasons.

"The thing with [having played] Dudley is that you get a call every now and again going, 'We’re looking for a really fat, rattish guy.' And then my agent has to go, 'Oh no, sorry, he’s changed,'" Melling told the Economist a few months ago. "And so I think that if my career was going to take off, it would take off in that sort of way. I had no desire for that to be my career, or to be my life, and to cash in on that. It was completely against everything that I wanted to be."

"My measure for fulfilling my ambition has always been the roles [I’m playing]," he added. "That’s the only thing to go by really. When that notion of career takes over the notion of why you’re doing it in the first place, that’s when it gets dangerous."

Either way, pretty impressive for a guy who used to be known as that awful bully from 'Harry Potter,' right?