Suggestions by @jaidynalexander

Paul Dano

as Peter Pettigrew in Harry Potter

James McAvoy

as Sirius Black in Harry Potter

Celia Imrie

as Madam Hooch in Harry Potter

Hannah Waddingham

as Professor Trelawney in Harry Potter

Stephen Fry

as Professor Slughorn in Harry Potter

Stephen Fry

as Professor Slughorn in Harry Potter

Olivia Colman

as Professor Slughorn in Harry Potter

Olivia Colman

as Umbridge in Harry Potter

Alfred Molina

as Moody in Harry Potter

Andrew Garfield

as Lupin in Harry Potter

Nicholas Hoult

as Professor Lockhart in Harry Potter

Rami Malek

as Professor Quirrell in Harry Potter

Nick Frost

as Hagrid in Harry Potter

Benedict Cumberbatch

as Professor Snape in Harry Potter

Jared Harris

as Professor Dumbledore in Harry Potter

Meryl Streep

as Professor McGonagall in Harry Potter