With therapy and antidepressants, gifted science student Brynn has climbed out of the depression her emotionally abusive ex left her in. She doesn't remember much about that time, and she's grateful. She's excelling in school again, planning for MIT, and even dating a sweet guy, Dex. Meanwhile, her mother, a pharmaceutical scientist, is about to see the public launch of her wonder drug Cortexia, which will revolutionize PTSD treatment. Then Brynn starts receiving anonymous texts that suggest she spent months working with an anti-Cortexia extremist group on a secret mission, triggering flashbacks of being abducted and interrogated. Brynn uncovers disturbing implications to Cortexia that mean she may not be able to trust anyone, including herself. This uneven psychological thriller is suspenseful, with a relatable but unreliable narrator and a gripping premise, but a third-act plot twist sends the story into a tailspin. The reveal is set up well and likely to shock even expectant readers, but the follow-through relies on villain monologuing and a disappointing ending that leaves invested readers with an unfinished story.

In this slow-moving thriller set in Annapolis, Md., high school sophomore Brynn Caldwell, a science superstar, starts having vivid nightmares and terrifying flashbacks of being kidnapped and interrogated, and possibly brainwashed. She has no idea what these scenarios are based on or whether the events in them really happened, nor does she know who is sending her mysterious text messages, which seem to be counting down to a bomb-s explosion. Brynn-s new boyfriend is afraid that Brynn is part of a homegrown terrorist organization that planted the bomb, which may be timed to coincide with the release of a brand-new drug, developed by Brynn-s mother, that is meant to help PTSD sufferers by erasing their memories. But Brynn doesn-t remember joining a terrorist group. In fact, Brynn can-t quite remember last summer at all. Could she be part of a plot against her own mother? The story takes a while to get off the ground, and the characters- motivations don-t hold together at the end, with an ultimate twist that strains credulity. But the premise, that a pharmaceutical company would falsify its tests, is more than conceivable, and Brynn is a likable protagonist. Ages 14-up. (July)

Gr 9 Up-Brynn Caldwell is finally recovering from a depression that left her floundering. but soon finds herself in the middle of a situation out of a Hollywood movie. Brynn's mother has just patented a new medication to treat PTSD by erasing memories. Brynn herself is a very advanced student with national chemistry awards to her credit. She is scared by memories beyond her grasp, and messages sent to her suggest that she has information, making her believe a terrorist group wants to stop the release of her mother's medication. Things become even more terrifying when she starts to think that she herself may have been a willing participant in developing a bomb. Brynn's struggle to determine the truth at all costs is what gives the story its appeal, despite convenient and somewhat absurd plot points that allow her to enter locked buildings and elude the police and her captors. VERDICT Recommended for general collections and teens looking for a fast-paced read. Betsy Fraser, Calgary Public Library, Canada