In the Harry Potter Movies (2001-2011), Snape’s costume was the only one that never changed. According to costume designer, Jany Temine:"Because, it was perfect. When something is perfect you cannot change it.” She joined in Prisoner of Azkaban and changed most costumes except Snape’s.

Realniceguy1979 on July 14th, 2020 at 11:49 UTC »

Alan Rickman was perfectly cast into that role.

I_am_not_Elon_Musk on July 14th, 2020 at 12:52 UTC »

Black on black on black is always perfect.

TooShiftyForYou on July 14th, 2020 at 12:56 UTC »

Alan Rickman portrayed Snape in the coldest, most critical tone possible in comparison to the books.

Example after Harry spies on his memories.

Book: “YOU WILL NOT REPEAT WHAT YOU SAW TO ANYBODY!”

“But—I—“

“GET OUT, GET OUT, I DON’T EVER WANT TO SEE YOU IN THIS OFFICE AGAIN!”

Movie: “Your lessons...are at...an end.”

“But—I—“

“Get. Out.”