For fans of Holly Jackson and Jessica Goodman, this high-stakes thriller is set in a virtual-reality paradise turned hellscape, from a celebrated writer making their YA debut.

At the start of each school year, Madison Pembroke, the most popular girl at Lincoln Academy, sends out invitations to her epic birthday party in the form of custom forged spiral keys. For that one night, a few lucky teens get to enter Ametrine, a virtual paradise that hosts the party of the year-a wild, unforgettable celebration that will secure their social status in the real world. As Madison's hated ex-BFF, Bree Benson never receives a key.

Until this year.

Despite warnings from her boyfriend, Bree sees the invite as an olive branch, the perfect opportunity to rekindle her once-amazing friendship with Madison. But as the party games begin to turn provocative and violent, Bree finds that Ametrine might not be the decadent wonderland she was promised. And that Madison may have let Bree enter Ametrine, but she has no intention of ever letting her leave . . .

Kelsey Day's gripping debut shows that while best friends know each other the best, ex-best friends know how to hurt each other the worst.