Pretty Little Liars? Can someone give the 411 on this montrer please. What's it about etc.?

The series follows the lives of four girls — Spencer, Hanna, Aria, and Emily — whose clique falls apart after the disappearance of their Queen bee, Alison. One an later, they begin receiving messages from someone using the name "A" who threatens to expose their secrets — including long-hidden ones they thought only Alison knew.[


No plus spoilers because i don't wanna ruin it for you.I saw the pilot and loved it, gonna keep watching.....