He was a veteran star of the screen, but to a generation Alan Rickman will always be Professor Severus Snape, the surly potions master and unassuming hero of the Harry Potter series.
It's little wonder, then, that the stars and fans of JK Rowling's magical franchise have joined together to pay tribute to the actor, who passed away after a battle with cancer at the age of 69.
Fans led the charge, taking a pivotal Harry Potter scene and dedicating it to the man who played their beloved teacher.
Author JK Rowling tweeted that she was "shocked and devastated" to hear of Rickman's passing, describing his death as a great loss.
Michael Gambon, who worked with Rickman on screen and in the theatre, spoke of the late actor with great warmth on BBC Radio 4.
"Everybody loved Alan. He was always happy and fun and creative and very, very funny. He had a great voice, he spoke wonderfully well. He was intelligent, he wrote plays, he directed a play. So he was a real man of the theatre and the stage and that's how I think of Alan."
Meanwhile, Matthew Lewis, aka Neville Longbottom, shared a touching tribute to the actor on Instagram.
Emma Thompson, who played Professor Sybill Trelawney in Harry Potter as well as appearing opposite Rickman in Love, Actually, called him her "ultimate ally".
"What I remember most in this moment of painful leave-taking is his humour, intelligence, wisdom and kindness. His capacity to fell you with a look or lift you with a word. The intransigence which made him the great artist he was – his ineffable and cynical wit, the clarity with which he saw most things, including me, and the fact that he never spared me the view. I learned a lot from him."
Fellow Death Eater Jason Isaacs, who played Lucius Malfoy, said the news of Rickman's passing had knocked him for six.
"Sidestepped by the awful news today. The polar opposite of the icy, manipulating characters he became best known for, Alan was hilarious, warm-hearted and fabulous company. To witness his laser-like honesty and precision as an actor in the flesh was a rare privilege. A great artist and a lovely man."
And Evana Lynch – aka Luna Lovegood – remembered a man "so kind and generous in the moments he wasn't Snaping about."
His brother, Oliver Phelps, who played George, followed suit shortly afterwards.
Warwick Davis, who served on the Hogwarts teaching staff alongside Rickman as Professor Flitwick, also took a moment to remember him.
Even Jamie Campbell Bower, who played the young Gellert Grindewald in Harry Potter and The Deathly Hallows, had something to say on Twitter.
In his post, he expressed his sadness at the actor's passing.