Yarrow (brown hair) goes to a posh school named Oak's Academy. Pearl is the "leader of Oak's" every girl wants to be her. Yarrow has been forced to be one of Pearls "henchmen" since she started at Oaks.
One day a new girl named Lark comes into school. Pearl tells Yarrow to be mean to her so she will leave the school. Yarrow doesn't agree with this because for some reason she feels like she's known Lark for a very long time.
After class Lark goes up to Yarrow and says "Hello Rowan" Yarrow gets confused by this but the name Rowan makes her feel something she hasn't felt before, complete.
Later that night Pearl invites Yarrow and Lark to sneak out to go to a party. Little do they know Pearl has a plan to get rid of Lark