Two new mystery novels to read in October

If you’re a fan of detective fiction, you know there’s a genre to fit any mood. Do you want to get lost in a psychological thriller? Crack open a police procedural? Get immersed in a historical mystery series? The possibilities are endless. Two new mystery novels offer distinctive recreational reads: Olivia Blacke’s cozy “Death at the Door” and Tom Ryan’s cold case “We Had a Hunch.”

Olivia Blacke’s “Death at the Door” is the second novel in the Ruby and Cordelia cozy mystery series. This is Blacke’s third series; she is also the author of the Record Shop Mysteries and the Brooklyn Murder Mysteries.

In the 2024 debut novel “A New Lease on Death” (winner of the 2025 Anthony Award for Best Paranormal Novel), 20-year-old Ruby befriends the previous occupant of her apartment, 40-something Cordelia, who had died there under mysterious circumstances and now inhabits the place as a ghost. (The first novel is entertaining but not a prerequisite; Blacke includes enough contextual background to make “Death at the Door” stand on its own.)

Most people never know that the invisible Cordelia is around, but Ruby, who loves true crime podcasts and has always believed in ghosts, can sense when she is nearby. Their evolving friendship bridges both liminal and generational lines and is a high point of this story.

“Death at the Door” is told in alternating chapters by each woman, a style that provides separate perspectives — Ruby’s perennially upbeat view and Cordelia’s cynical one — and also gradually reveals more of each woman’s back story. Through conversations, which the pair conduct in inventive ways, Blacke also shows how their very different world views sharpen their crime-solving abilities: a clue that one might miss, the other one sees.

Their lives have become quite entwined. Ruby now works as office manager at TrendCelerate, the same downtown Boston tech firm where Cordelia worked.

A nearby deli is the company’s catering place, and everyone’s favorite delivery guy is Marty, who on the sly supplies some of the staff with under-the-counter prescription drugs along with their sandwiches. That is, until he turns up dead one day in the company bathroom from an apparent overdose.

The police are satisfied with that finding but Ruby and Cordelia are not. As they dig into Marty’s past, they turn up more questions than answers.

This tale contains many well-thought-out details, from TrendCelerate’s modish office space design and its quirky collection of employees to Cordelia’s relatively new experience as a ghost. Her spirit talents, like seeing in pitch dark and traveling to a location just by thinking about it, are fine skills for any detective.

Cordelia is surprised, though, by how few ghosts there are in Boston; for such an old city, she has only met two. Why someone becomes a ghost is left enigmatically open-ended.

Unfortunately, the Boston of “Death at the Door” could be any large city. Beyond name-checking beloved Dunkin’, there are no distinctive buildings or neighborhoods to provide local texture. But even with that, the novel breezes along to land at a tantalizing cliffhanger of an ending. We haven’t seen the last of this earthly and ethereal duo.

If you’re in the mood for a deeper read, Tom Ryan’s “We Had a Hunch” is a cold case mystery rounded out with sympathetic and multifaceted characters. Ryan has authored young adult and adult mystery novels. His YA novels —2019’s “Keep This to Yourself” and 2020’s “I Hope You’re Listening” — have won multiple awards. His best-selling adult mystery novel “The Treasure Hunters Club” was a 2025 Edgar Award nominee. “We Had a Hunch” is his second standalone adult mystery novel.

The tale is set in the fictional Massachusetts town of Edgar Mills. From the police station to the diner to the Edgar Mills River Trail, Ryan has created a comfortable Greater Boston suburb.

Back in 2000, before the tragedy that changed their lives, twins Alice and Samantha VanDyne were magazine-cover famous as teen detectives who had helped their police chief father solve a string of non-violent crimes. Not nearly as well-known, by choice, was their friend Joey, a quiet computer nerd who helped the twins on some of their cases.

That same year, crime in Edgar Mills escalated to murder. Over a few months, three people in town were killed, with similar evidence left at each crime scene. The teen detectives devised a plan to trap the serial killer, but it all went wrong on one horrific night, resulting in the death of Alice’s boyfriend and the twins’ father.

Jump to 2025: Samantha, Alice and Joey are in their 40s, each grappling with an array of mid-life issues. And someone is again committing murder in Edgar Mills, leaving the same type of evidence as 25 years ago. But the convicted killer has been in Walpole Prison since his trial. He’s always proclaimed his innocence, and now says he has new information on the case, which he will only share with Sam, Alice and Joey.

For the former classmates, this meeting opens old wounds and makes for an uneasy reunion. Samantha, who still blames herself for her father’s death, had fled Edgar Mills for Los Angeles. She had a brief career as a reality TV star people loved to hate; she now enjoys a life out of the spotlight.

Alice stayed in town and married Levi, the brother of her murdered high school boyfriend. She is currently trying to ignore a vague dissatisfaction with her marriage, as well as mounting frustration with their moody 15-year-old son Will.

From high school, Joey went to MIT and then to a Cambridge-based tech company, where he’s made a pile of money from an app he helped develop. Happily married to Austin, whose kindhearted nature helped Joey shed his “anxious workaholic” persona, Joey has grown bored at work and is ready for a change.

Samantha, Alice and Joey soon find their dormant detective interests completely reawakened. As the tale progresses, they also emerge as fully realized, ordinary people whose decisions, disappointments and triumphs are so believable they could carry a story even with no crime to solve.

There are a lot of characters in “We Had a Hunch,” and it’s a credit to Ryan’s story-building skills that it’s easy to keep track of everyone. The main characters are kept nicely foregrounded, aided by chapters individually voiced by the three.

Other relevant townspeople are gradually introduced until there is an intricate interlocking network of social ties, including the twins’ mother, a high school friend who is now police chief,  a sad-sack high school friend turned effortlessly cool adult and a young teen with a popular TikTok account who seems to be everywhere covering crime updates. This also makes for some nicely sketched contrasts between how today’s tech shapes the perception of a criminal investigation and the pre-social media world of 2000.

With its psychological curves and emotional twists, “We Had a Hunch” will keep you turning pages right to the truly surprising conclusion. After the superbly done “The Treasure Hunters Club,” I’d wondered how Ryan’s sophomore endeavor would do when stepped up to the plate. Mystery solved: “We Had a Hunch” knocks it out of the park.