He may not be the biggest character in the franchise - in any sense of the word - but Professor Flitwick has a valuable part to play in the Harry Potter series.
The little chap with a big heart heads up Ravenclaw House and is a powerful wizard, mastering charms and performing one of the toughest of spells: a non-corporeal Patronus.
So was anyone else a little freaked out in the movies when he just... CHANGED?
Professor Filius Flitwick begins the Harry Potter series as a white haired little man, played by the ever-fabulous Willow star Warwick Davis. Then, suddenly, in the third movie and beyond he's a much younger-looking guy - though still played by Davis - with a natty mustache.
This younger model is very much accepted as the 'proper' Flitwick now - at least by LEGO, who based their Flitwick minifigure on the Azkaban-and-onwards version.
But WHY?! Well, it's all down to Harry Potter and the Prisoner of Azkaban director, Alfonso Cuaron. I'll leave it to Warwick Davis himself to explain:
When it came to the third film, of course the looks of the whole films had changed.
Alfonso really wanted to put his mark on the films. And then a lot of things altered: anything from character looks, to the actual layout of Hogwarts itself.
And another thing was happening at the same time. There wasn't really anything for Flitwick in the script at all, and I got a call one day from the producer, saying basically, "There's nothing for you, but we'd love you to be in the film all the same. How do you fancy coming in and doing a kind of cameo in the film as somebody else?"
And I said, "Well, that's great, thanks for asking. I'm always thrilled to be part of all of this, anyway." So, I went in for a meeting with Alfonso, the director, and Nick Dougland, who's the make-up supervisor, and we came up with this new look for this character who would be basically the conductor of the Frog Chorus in the Great Hall. And so, we went with that.
It's as simple as that!
But wait... are they the same person?
There's been debate over whether the original Flitwick and the younger, grumpier choir master are the same character, but they are confirmed as the same character more than once, most obviously when McGonagall addresses him as 'Filius' in Deathly Hallows II.
What's really interesting is that J.K. Rowling never intended for Flitwick to be a little person at all! She said in an interview:
I must admit, I was taken aback when I saw the film Flitwick, who looks very much like a goblin/elf (I’ve never actually asked the film-makers precisely what he is), because the Flitwick in my imagination simply looks like a very small old man.
So, Potter fans, let's pour one out for the dearly departed white-haired Flitwick, ousted by the creative vision of a Potter director. Oh, and Flitwick's favorite ever drink is ice, soda and cherry syrup with an umbrella, so make sure you're drinking the right stuff!
Which Professor Flitwick did you prefer?
Sources: Harry Potter Wikia