Everyone knows Alison DiLaurentis, queen bee of Rosewood and famous "murder" victim. But what about Iris DiLaurentis, Ali's 15 year old sister? In the years Ali's been "missing", Iris was the only one she contacted. However, now that the liars know she's alive, Iris must try to convince Ali to come back and the liars to not fear -A. Because Iris knows everything. She's the missing link.