A/N -
So before DH came out, there was a fan theory that Mcgonagall was a Death Eater. Obviously, it turned out she wasn't.
But what if she was.
JKR said that she was a Hatstall between Gryffindor and Ravenclaw.
But what if she wasn't.
What if she was a Hatstall between Gryffindor and SLYTHERIN.
What if she really belonged in Slytherin, but because she was a half-blood, she thought she could do better in Gryffindor.
What if she was a double agent.
What if she was another Snape.
What if she passed information from Voldemort to Dumbledore, who thought she worked for him.
What if she passed information from,Dumbledore to Voldemort, who thought she worked for him.
What if she worked for neither of them.
What if she was a better schemer, a better manipulator, a better SLYTHERIN, than any of them?
What if Voldemort had won?
She would have revealed herself as his top Death Eater.
What if the Order won?
She would be the new headmistress of Hogwarts, and no one would suspect a thing
What if Mcgonagall was the one who won, in the end?
Red Queen Chapter 1
They met on the Hogwarts Express, first year. The slim girl with her dark hair in a neat pony, and the pale boy with his frayed, second hand trousers. She tells him that her entire family have been in Gryffindor, and her parents expect her to be there too, although she thinks she would be a better Slytherin. He tells her that he was brought up by Muggles, but despite that, he also thinks he will be a Slytherin. They decide then, that whatever houses they are in, they will stay friends.
After all, they are, although they don't know it yet, the greatest minds of their generation.
They sit in the same boat, and stand together, waiting to be Sorted. She is called up first.
" Mcgonagall, Minerva!"
The Hat slips over her eyes, and all is quiet.
" Well, well. Minerva Mcgonagall, a direct descendant of Godric Gryffindor himself. Should I bow?" asked the Hat snidely in her ear.
" But no, you aren't a Gryffindor."
" No. I never thought I was."
" You are ambitious, I see. Cunning, willing to manipulate, to scheme, to let others do your dirty work. My dear, there is only one place you could POSSIBLY belong... SLY"
" No!" Minerva's emerald eyes widened, and the Sorting Hat shut its mouth with a snap.
" No. I know, I really only fit in Slytherin, but my parents would never accept it. I HAVE to be a Gryffindor." The Hat was silent.
" Are you not brave enough to rebel against your parents, child?"
" No. I never claimed to be. But you will put me in Gryffindor."
The Hat huffed. " Intresting... a Gryffindor who isn't brave enough to be a Gryffindor... Oh, well! GRYFFINDOR!" Minerva barely heard the next names, her mind far away, until she heard his.
" Riddle, Tom!"
The Hat barely touched his head before... " SLYTHERIN!"
Minerva was the only lioness who clapped.
They are the Slytherin and the Gryffindor, the oddity of the school. They walk together in the hallways, followed by stares, his hands shoved in his pockets, her arms full of books.
Minerva gets out her chessboard. Tom blinks at it.
" Are magical chessboards always like that?"
Minerva laughs. The chess board has white, black and red squares, a deep marble black that you could almost fall into, white crystal, sparkling enough to see your own face in, and a dignified mahogany red, like autumn leaves. There are three sets of pieces too, and Minerva tells Tom that this chess set actually belonged to Godric Gryffindor himself, and it has three different colours because Slytherin gave it to him as an enchanted gift.
" Red versus black." She tells the board, and the white pieces and squares shimmer before disappearing. Minerva plays red. Tom plays black.
" Red Queen take Black Knight, and checkmate." She tells him. Tom stares.
" How..." He grins at her. " You're the first to have beaten me in a long time." He winks. "Are you sure you aren't a Slytherin, my Red Queen?"
That is the birth of his name for her. Minerva chuckles.
" Tom, don't you know? Only the best Slytherins can pretend to be Gryffindors."