I didn't read the first one in the series, and probably won't. But I will buy this series for my high school because the fans of Gossip Girl and the A-List will love it. And I like that there is a mystery and a murder or two thrown in so I can recommend this to girls who are looking for a mystery but don't like adult titles yet.
Basically, picture The Gossip Girls. Four friends who are snotty, rich, skinny, and almost perfect do everything their ringleader Allison tells them to do. But she ends up missing a few months after a late-night prank. The girls still swear to keep the secret about the prank and go their separate ways. Three years later, Allison's dead body turns up and the girls have to come together to unite against the mysterious -A who is sending them scary text messages. "A" knows all their secrets. How are they going to escape from A? When she/he dies? But just when they think everything will improve, A sends one more message.
You'll have to read Perfect, #3 in the series, to see how it ends.