When the first letter appears in Kay Anderson’s locker,it carries one instruction: dye your hand blue. She definitely shouldn’t follow it. Kay doesn’t have time for secret societies: as a scholarship student at up-and-coming Manhattan prep school Davison Highshe knows her job is to work hardget into Northwesternand ignore her wealthy classmates’ fun-filled Instagram stories. Besidesher first and only real friend at Davison died suddenly freshman year. StillKay’s intriguedso she stains her palms with ink to join the mysterious Blue Hand Girlssharing an unspoken thrill with the classmates who do the same. More letters show upassigning risky initiation tasksand Kay realizes the group is set on exposing the shady business that Davison’s founders would rather keep hidden–things that her dead friend might have known about. But the anonymous instructions also demand the girls reveal their own secretsbonding them all too close to abandon the society. Soon Kay doesn’t know who’s more dangerous: the powerful people who run her schoolor the Blue Hand Girls themselves. And then there’s Zola Wolfethe beautiful redhead in Kay’s Calculus classwho’s never been seen with a blue handand who just might become her girlfriend. Yet Kay can’t help but wondereven as she kisses her on the roof of Davison Highif Zola is the most dangerous of them all.