Sam & Ilsa's Last Hurrah

The New York Times Bestselling duo behind Nick & Norah's Infinite Playlist and The Twelve Days of Dash & Lily return with twins out to throw the party of a lifetime--or at least the best party of high school

Siblings Sam and Ilsa Kehlmann have spent most of their high school years throwing parties for their friends--and now they've prepared their final blowout, just before graduation.

The rules are simple: each twin gets to invite three guests, and the other twin doesn't know who's coming until the partiers show up at the door. With Sam and Ilsa, the sibling revelry is always tempered with a large dose of sibling rivalry, and tonight is no exception.

One night. One apartment. Eight people. What could possibly go wrong? Oh, we all know the answer is plenty. But plenty also goes right, as well...in rather surprising ways.

RACHEL COHN is the author of critically acclaimed YA novels Very LeFreak, You Know Where to Find Me, Cupcake, Shrimp, Gingerbread, and Beta. A graduate of Barnard College, she lives and writes in Los Angeles. Find her online at rachelcohn.com and @rachelcohn.

DAVID LEVITHAN is a children's book editor in New York City, and the New York Times bestselling author of several books for young adults, including Boy Meets Boy; Will Grayson, Will Grayson (with John Green); Every Day; and Another Day. Follow him at davidlevithan.com and @loversdiction.

Rachel and David's first four collaborations were Nick & Norah's Infinite Playlist, Naomi and Ely's No Kiss List, Dash & Lily's Book of Dares, and The Twelve Days of Dash & Lily.