Stacy Friedman has just had the most amazing summer of her life. At camp, she and her best friend, Lydia, met a girl who trained them in all things cool. Equipped with this new knowledge, they're set to make an unforgettable back-to-school debut.

Unfortunately, Stacy and Lydia aren't the ones turning heads at Jefferson Junior High. Everyone clamors around their other best friend, Kelly, who has transformed from not-so-cool to so-very-cool in three months. Stacy and Lydia are happy for her, but shocked when Kelly gets super cozy with Kym and her popular clique, The Chicas. Worst of all, Stacy and Lydia are the only ones NOT invited to Eben's Hollywood-themed bar mitzvah.

But Stacy refuses to accept their social blacklisting and decides they should crash Eben's bar mitzvah. Before the party ends, Stacy and Lydia will have gone undercover, posed for paparazzi, and faced off with the Chicas. They'll also find out exactly who their true friends areand aren't.