Harry Potter and the Prisoner of Azkaban
Professor Minerva McGonagall
Professor: Transfiguration; Deputy Headmistress
House: Head of Gryffindor
When we first met the Hogwarts Deputy Headmistress, she seemed completely no-nonsense and super strict. She's like a cross between a stern British nanny and a forbidding librarian. But we've slowly discovered another side to our indomitable head of Gryffindor over the years, and in this book we feel that we can confidently say this: McGonagall is one of the funniest characters in the entire series. No, really. Don't believe us? Check out these passages:
[Lee Jordan:] "Cho's Comet is just no match for it, the Firebolt's precision-balance is really noticeable in these long –"
[McGonagall:] "JORDAN! ARE YOU BEING PAID TO ADVERTISE FIREBOLTS? GET ON WITH THE COMMENTARY!" (13.2.34)
McGonagall has mastered the art of sarcasm. And she's especially funny when she isn't really trying to be funny – her temperamental shouting at the mildly inappropriate Lee Jordan is always great, for instance.
But McGonagall really comes to life for us, as a human with flaws as well as with a sharp sense of humor, when she's talking about or interacting with the airhead Professor Trelawney. These two are polar opposites and it's painfully obvious that McGonagall can't stand Trelawney, even though she makes a half-hearted effort at being polite to her colleague.
"But surely you already knew that, Sibyll?" said Professor McGonagall, her eyebrows raised.
Professor Trelawney gave Professor McGonagall a very cold look.
"Certainly I knew, Minerva," she said quietly. "But one does not parade the fact that one is All-Knowing. I frequently act as though I am not possessed of the Inner Eye, so as not to make others nervous."
"That explains a great deal," said Professor McGonagall tartly. (11.2.165-168)
It's like McGonagall's proper and professional façade comes into conflict with her sarcastic, smart, and sharp-witted inner self at times. McGonagall really embodies the book's theme of appearances being deceiving, and she's one of the book's more emotionally complex minor characters.
One last tidbit that we find fascinating about McGonagall: her connection to one Hermione Granger. These two are like two peas in a pod, in a way. Both are super smart Gryffindors, both have a fondness for rules (though they don't mind breaking them if need be – see McGonagall's desire to win a Quidditch match beating out her desire to restrict Harry to the castle for his own safety – 9.2.11). But we especially see their connection in their mutual dislike of Trelawney. Both of these logical and rational Gryffindor ladies have little patience for the mystical Trelawney.