"Heidi is making new friends at Broomsfield Academy—in particular, a popular girl named Isabelle. But it turns out Isabelle has a big secret that Heidi discovers by accident! Heidi promises to keep the secret, but as more time goes by, it becomes more and more difficult…especially with nosy Melanie Maplethorpe snooping around. This secret is huge. Will Heidi be able to keep her promise?" --publisher's website