Based on looks alone, Regina George (Rachel McAdams) seems like she’d be anything other than a Scorpio. But this moody character is a water sign through and through. Scorpios are intense, to say the least. Take one look at how characters respond when Regina’s eyes are trained on them, and you’ll see that Scorpio effect in real time.
She’s incredibly intelligent and independent; she knows exactly how to manipulate any situation to have a favorable outcome. And she’s jealous like a Scorpio, too, which ultimately leads to her downfall.
But that Scorpio loyalty runs deep. So even at the end of the movie, she’s still on good terms with her old Plastics crew.