Don’t Let Him In is a story that makes you wonder just who might be watching you from the shadows – and why.

Our story begins with an end. Flowers are delivered to the home of successful entrepreneur Paddy Swain. They are unwelcome. His wife, Nina, and daughter, Ash, have all the posies they can stand. There are no vases available for this latest batch, one more fragrant bouquet sent in condolence as they mourn the man who had always been the life of the party and the heart of their family.

Even as she shoves this latest offering into an already overcrowded arrangement, twenty-four-year-old Ash finds it impossible to believe that Paddy was murdered in such a gruesome and meaningless manner. He’d been pushed into the path of an oncoming train by a man struggling with mental illness, and she can’t reconcile the pointlessness of it with the over-the-top, king-of-the-world energy her father had always exuded.

Less than a year later, Ash wonders if her inability to move beyond her grief has kept her from accepting the new man in Nina’s life. Ash is uncomfortable with the fact that Nick has ingratiated himself to the family by claiming to be an old acquaintance of Paddy’s, and that the start of this new relationship was a condolence card with the gift of a lighter that had allegedly belonged to her dad long ago. It was an odd thing for a casual friend to have kept for twenty-odd years, and Ash can’t shake the suspicion that there is something off, something sinister about charming Nick and his generic stories of the past. An incident from just before her father died has left Ash questioning her own judgement, but she figures there’s no harm in checking with others from her dad’s youth and seeing what they remember about Nick.

In a village a short drive away from Ash is Martha, a small-town florist with an absentee husband. Al has been working long, weird hours lately and fallen into the habit of not returning her calls and texts for days. She struggles to keep up with her three kids while managing her thriving business independently and is growing increasingly resentful of Al’s smooth but uninformative responses to her reasonable questions. The night she has to call a friend to drive her and her sick youngest child to A&E because Al has the car is the final straw. It’s time for her to start searching for answers as to just why Al’s job is keeping him away from both his phone and his family.

I imagine most readers think they know the score by this point, and in some ways, you are right. But Ms. Jewell is a consummate professional, and she turns what could have been a mundane charade into a richly layered mystery, with Martha and Ash discovering completely unexpected twists.

The tale is told from multiple points of view, which works well to give us a comprehensive look at both how the villain operates and how strong, capable women are pulled into the bizarre situation the story revolves around. Ms. Jewell’s skill at creating unique voices for her cast keeps the head-hopping from turning confusing and disjointed, and it helps that the bulk of the narrative is told by our primary protagonists, Ash and Martha. I adored Ash, who is a lovely combination of youthful insecurity, determination, and intelligence. She’s clever enough to realize something’s off but also resourceful enough to recognize she’ll need outside help to figure it out. Once she begins to connect with Paddy’s past, she finds an older and wiser woman to be her confidant. Together, Ash and Martha carefully follow up on each clue, building a case before confronting Nick or Nina with what they have discovered.

Martha is a more complicated heroine. Many times when a crime is committed, the victim is left to wonder why they hadn’t been smart enough to avoid being victimized, and that is especially true with someone in Martha’s position. The story does a nice job of presenting her as a savvy, busy woman whose kindness makes her vulnerable.

Creating relatable, likable characters and having their decency catch them up in bizarre, dangerous situations is a hallmark of Jewell’s work. Another strength is how she can take an ordinary suburban world and slowly turn it into a grey, gloomy, gothic atmospheric setting. At the start, we are told the day of Paddy’s funeral is cloudy and dreary, a direct contrast to the sunshine-loving, fun man Paddy was, as though he had taken all the light and warmth with him. The author amplifies that perception throughout the novel, as though his death creates the dark world Martha and Ash soon inhabit. It gives the tale an increasing sense of ratcheting danger, making it an enthralling reading experience.

I also appreciated the way the author delicately explores how believing in our own exceptionalism can be the bait that keeps us mired in a trap long after we’ve discovered it’s a danger. For Martha and a character introduced late in the novel, the idea that they are somehow special and different keeps them stuck in a situation from which they’ve had multiple opportunities to escape.

That said, this particular novel is not Jewell at her strongest. It’s pretty clear from the beginning that the villain is less troubled than monstrous. They aren’t two-dimensional at all, simply abusive and narcissistic. We know (a little of) what is happening from the start, but it stays interesting up to the last page because we get surprise after surprise as Martha and Ash dig deeper. At first, this was wonderfully thrilling, but as we approached the finale, I experienced shock fatigue. Too many unbelievable things had happened for me to maintain my suspension of disbelief during the intervention-style denouement and the events that follow. I also struggled to believe in the behavior of one of the characters/victims in the last quarter of the book. The plot hinges on her doing what she does, but what she does didn’t seem credible.

Don’t Let Him In is one of those stories that’s hard to grade. There are problems, such as the above, plus other little foibles that keep it from being an A read. On the other hand, it holds the attention from start to finish. You might find some of the events completely implausible, but it won’t matter because you want to see the conclusion and arrive at closure for all you (and the characters) have been through. I strongly recommend it to mystery fans despite its imperfections.

Note: This book deals with manipulation, gaslighting, violence against women, and abuse of individuals with mental illness.