A Dr. Zol Szabo Medical Mystery Books in Order

At the center of this series is Dr. Zol Szabo, a Hamilton public-health doctor and former chef who keeps getting pulled into outbreaks that turn into murder cases. He works on the Niagara Escarpment in southern Ontario, where hospitals, labs, restaurants, retirement homes, schools, and city politics all sit close enough to feed the next crisis. These are medical mysteries, but they move with thriller energy. Once contamination starts, nobody has much time.

Zol is smart and stubborn, but he never works alone. Hamish Wakefield brings infectious-disease expertise and an oddball streak. Natasha Sharma does the hard grind of epidemic work. Colleen, a private investigator, can follow a trail outside the lab. Zol's son Max and the people around him keep the books tied to everyday life, not just case files and lab results.

The science matters here.

Pennie writes outbreaks the way a real doctor would, as a mix of clues, paperwork, exhausted judgment calls, and public panic. One book starts with what looks like mad cow disease in Tainted. Another turns fatal food poisonings at Camelot Lodge into a larger criminal puzzle in Tampered. In Up in Smoke, teens in Ontario's tobacco country are dying from liver failure, and the investigation pushes Zol toward the illegal tobacco trade and dangerous people who want him silent.

The later books widen the stage without losing the same pressure. Beneath the Wake strands Zol on a luxury cruise ship in the Indian Ocean, where a lethal infection among the crew turns a holiday into a race against quarantine. Bitter Paradise brings the story back to Hamilton and pairs Zol's search for the source of vaccine-resistant polio with the story of a Syrian refugee surgeon trying to rebuild his life as a barber. Across the series, the threat is never just the microbe. It is also money, ego, secrecy, and institutions that do not like being embarrassed.

Nobody gets to stay comfortable for long.

If you like crime fiction with real medical texture, this series delivers that without turning cold or clinical. The books are tense and fast, but they also have humor, family strain, and a lot of sympathy for people doing difficult work under pressure. Start with Tainted if you want the full arc, then read in order.