At first, MOTHER DAUGHTER SISTER STRANGER seems fairly straightforward. In fact, after the first few chapters, I was wondering how Hank Phillippi Ryan would make it suspenseful. But once the action starts, it's pretty much nonstop. I raced through the last three-quarters of the book to find out what was going on. While I figured out some of it, most was well hidden in the morass of guilty people, long-held secrets, family betrayals, deaths, and even a serial killer. This is not a novel for readers with delicate sensibilities.

Eliza and Bea Ramsey were used to relying on each other after their parents were killed in a small plane crash that almost took their lives too. They recovered under the care of their Aunt Margaret, and while Eliza would like to be close to Bea, Bea's lifestyle and choice of partner have made that difficult. But one thing that always unites them is the Ramsey Remembrance Day, which they “celebrate” on the anniversary of their parents' passing.

"This is a story that truly will keep you up late at night in your rush to find out the resolution. While you might guess some of it, I predict that few will figure out the entirety of this cleverly plotted, thrilling mystery."

Both girls have successful lives. Eliza is a book agent specializing in romance novels because she loves happy endings. Bea has become a fashion influencer and has closets overflowing with expensive couture. She hasn't been as open with Eliza since she married Kyle, who is 10 years her elder and very bossy. So when Bea presented Eliza with Piper, the five-year-old girl she and Kyle had just adopted, Eliza was blindsided and disappointed, but not shocked that Bea hadn't told her anything leading up to the adoption. She also hasn't shared much about her recent divorce from Kyle.

At the beginning of the novel, Bea doesn't arrive to pick up Piper as agreed. Piper is worried and keeps looking out the window. To distract her, Eliza asks Piper, “What's the happiest ending you can imagine?” because that's how Eliza views life. She even imagines what happens in books with not-happy endings after the last page. How can a sad ending be turned around? Piper thinks pizza sounds like a happy ending, and it helps. At that moment.

But as the days pass, and Bea doesn't show up, answer her phone or respond to texts, Eliza and Piper are quite worried. And because Eliza is the adult, she has to reassure Piper that everything will be okay. They go to Piper's house, and Eliza sees that all the clothes in Bea's huge closet aren’t there. Has Bea intentionally disappeared? Or has she been kidnapped, or maybe even killed?

There is much history that is shared about the Ramseys and the girls' very successful parents. Their mother was a lawyer and a judge. Their father was a professor, as well as a pilot, and they flew to the Berkshires in their small private plane. They spent summers there, but we learn that a serial killer had haunted Eliza and Bea’s teenage years. During the summer at their vacation home, girls had been murdered. Their parents didn't allow them to be outside after dark, and everyone wondered who the Greylock killer was. 

There's also Whitney Hart, Eliza's boss and head of the literary agency. She's become very involved in helping Eliza with Piper now that Bea is missing. It's quite suspicious. Whitney and Eliza had never been close. So why does Whitney seem so interested in Piper and Bea? When Eliza finds a manuscript about the Greylock killer, more questions arise.

Ryan's masterful use of Eliza's first-person narrative ratchets up the tension as we feel her fear when mysterious notes appear, a shadowy figure moves the curtains in her apartment as she and Piper watch from below, and she doesn't know where to turn or where is safe. Finally, they flee to the summer home in the Berkshires, where the novel comes full circle, and all of Eliza's questions will be answered.

This is a story that truly will keep you up late at night in your rush to find out the resolution. While you might guess some of it, I predict that few will figure out the entirety of this cleverly plotted, thrilling mystery.