TESS Gerritsen once said a good thriller isn’t about violence or bloodshed, it’s about making the reader feel off-balance and as if something isn’t quite right. And that’s just what the doctor-turned-best-selling author has achieved in Last To Die, the 10th instalment in her Rizzoli and Isles series, in which she takes creepy to new levels.

"Write what you know" is the general rule when tackling a book and it’s this premise that has made Gerritsen immensely readable and popular. Her knowledge of emergency and autopsy rooms lends gravitas to her scene-setting and her attention to forensic detail makes the stories plausible.

Last To Die opens with the slaying of a retired investment banker and his family in Beacon Hill, Boston. Homicide detective Jane Rizzoli and medical examiner Maura Isles are called to the scene, where they find 14-year-old foster son Teddy Clock, the sole survivor of the massacre. It’s a case of déjà vu for Teddy as his real family was killed aboard their sailboat two years previously.

Soon after, Maura heads off to Evensong, a boarding school in rural Maine, to visit Julian "Rat" Perkins, who saved her life in a previous book, Ice Cold. The school’s remote location and top security lead Jane to believe it’s the ideal place to keep Teddy safe while she hunts for his foster family’s killers. But Evensong is no ordinary school, and its students are not ordinary either. All of them have been victims of violent crime and within the safety of the school learn the secrets and skills of survival in a dangerous world.

It’s run by the Mephisto Society, a group of dedicated individuals whose lives have been tragically touched by what they consider to be the collective action of evil. While there, Maura makes the startling discovery that two other students have stories very similar to Teddy’s.

When the pupils discover three blood-spattered twig dolls hanging from a tree in the school’s property, it soon becomes apparent that there could be a connection linking the three orphans. Jane knows that someone wants these children dead — and the threat could well be from somebody within the institution itself.

One of the series’ strengths is the interplay between Jane and Maura. Jane is dealing with her mother’s upcoming wedding (despite still being married to her father), while Maura is questioning whether she fits in with the Boston crowd. She seems to have developed a special connection with Julian, president of Evensong’s Jackals Club, an odd group of amateur detectives who aim to show Jane and Maura a thing or two about crime solving.

Gerritsen has the ability to ratchet up the chill factor from the first word. There are twists and turns — and red herrings — aplenty, and you’ll find yourself forgoing any social engagements if it means getting to the end that little bit quicker.