The preface begins by asking the reader to imagine that it’s a few years ago during the summer between seventh and eighth grade. A cute girl has gone missing, and her face is now on the side of a milk carton. She’s not a beauty pageant participant, but rather a regular girl “like you” (1). The preface then cuts to best friends Aria Montgomery, Alison DiLaurentis, Emily Fields, Spencer Hastings, and Hanna Marin gathering at Alison’s house on the last day of seventh grade. They became friends doing volunteer work at Rosewood Day School’s charity drive. Alison is the most popular and the leader of the group. The other girls felt awkward and “noticeable for all the wrong reasons” (4) before Alison started talking to them. Now, over a year later, they are not only best friends but “the girls of Rosewood Day” (4). The girls are bonded by many good experiences together but also a secret that they never care to talk about again.

The girls head to Spencer’s guest house, which is next door to Alison’s house. On the way, they all start yelling “Not it” (5), which is a game they play to avoid talking to “anyone ugly, uncool, or unfortunate near them” (5).