When a famous forensic scientist dies at the lab where Ruby Rose's father works as a janitor, the evidence seems to point to him as the murderer. Although he seems to have had no motive to kill Dr. Ramachandran, police find vials of deadly poisons in his locker. Ruby, who sorely misses the rural area from which her family has moved, bands together with Rex, another resident of the housing projects where she now lives, and Mrs. Whitmore, a reclusive elderly woman who has a few secrets of her own that will help her solve the crime and free her father. I enjoyed the first half of the book more than the second one since all that climbing up and down in hidden portions of the building while someone else follows them seemed rather absurd. When the real criminal is revealed, I was not able to buy the big reveal or motivation for murdering Dr. Rama. I know the academic world can be deadly, but I never realized it could be so murderous. My favorite part of this uneven scientific mystery were the interviews with Mrs. Whitmore that bookended the story. My least favorite parts were the stilted dialogue, the references to Ruby's past, and her father's seeming helplessness. Still, many middle graders will enjoy this title.