Don’t Look Back by Jennifer L. Armentrout (review)

Until Cassie moved to town, Sam was happy to be the privileged but nice tagalong to her twin brother, Scott, and his best friend, Carson, whose father worked for their family. Under Cassie’s influence, though, Sam became the quintessential mean girl, lording her money and social position over everyone in her high school, fighting with her mother, disdaining Carson, and dating Del, a boy whose status matched her own. Now Sam has resurfaced alone after she and Cassie have been missing for four days, and she remembers nothing of her old self and her old life; she quickly realizes this memory loss is a blessing, given how despised she was. She is also distressed by a series of notes that keep appearing in odd places warning her not to remember the details of the night when both girls disappeared and only one returned. Meanwhile, she finds herself drawn to Carson, and snatches of memory return to remind her that she was beginning to have real feelings for him before Cassie worked her transformative magic on Sam’s personality and priorities. While Sam sifts through clues and half-formed memories to solve the mystery of her own personality conversion as well as Cassie’s disappearance, the posh school setting with a serious mean-girl problem provides an entertaining if familiar context. Cassie’s brother and his girlfriend stabilize the ground under Sam’s newly insecure social feet, narratively speaking, and her growing romance with Carson rounds out the genre blend as murder mystery merges with prom fisticuffs, and family tragedy with mean-girl melodrama. Recommend this to readers who prefer their soap operas set in high school.