Question: Who is the actor that plays professor lupin?
Disambiguated questions and answers: question: Who is the actor that plays adult Professor Remus Lupin in the Harry Potter film series?
Who is the actor that plays teenager Remus Lupin in the Harry Potter film series?
answer: David Thewlis
James Utechin
Natural Questions answer: David Thewlis (from the Wikipedia article "David Thewlis")