Rickman's death came as a shock to many. The beloved British actor was highly regarded by his peers as a legend of the stage and screen. His "Harry Potter" co-stars took to social media to pay their respects to the acclaimed star, remembered fondly as Professor Severus Snape.
Dumbledore actor Sir Michael Gambon told 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."
Daniel Radcliffe, the titular star of the franchise, posted a moving tribute to the late actor on his Google+ page, calling Rickman "undoubtedly one of the greatest actors I will ever work with." Radcliffe recalled how Rickman was one of the "first of the adults on Potter to treat me like a peer rather than a child."
J.K. Rowling, the author of the wildly successful "Harry Potter" series remembered Rickman for his indomitable talent on Twitter:
James and Oliver Phelps, who played Fred and George Weasley respectively, also took to Twitter to pay their respects to the actor who gave them an invaluable education in drama on the set of "Harry Potter":
Jamie Campbell Bower, who portrayed Gellert Grindelwald, recalled working with the veteran actor on his first-ever feature film, "Harry Potter and the Deathly Hallows: Part 1."
Warwick Davis, known for playing Professor Filius Flitwick in the "Harry Potter" films, took to Twitter to remember his good friend:
Emma Watson, who played Hermione Granger in all eight films, said she feels "lucky to have worked and spent time with such a special man and actor."
We'll be updating this list with more touching tributes throughout the day...
We raise our wands to the sky in honor of you, Alan. Always.