Thanks to NetGalley for a review copy in exchange for an honest review.

tl;dr
A complex mystery with many layers featuring a fun lead, and a somewhat less fun supporting cast.

About
Delia Ross has been many things over the course of her life. Currently, she's a spy for the NYPD, posing as a grieving widow in the hopes that they'll manage to trap an escaped fugitive. But as Delia digs deeper into the mystery, more mysteries arise, including several she thought she had buried.

What I Liked
I love a mystery with extra twists! Every layer that gets peeled back reveals more mysteries, all carefully plotted. There are a lot of things to keep track of, but they all come together for a satisfying conclusion, and an even more satisfying epilogue. Delia is a fun lead - ambitious, bold, and direct, and her personality really shines. Her sister Maude is a cranky delight, and the two of them are truly a powerhouse of detective work. Setting and scenes are easily imagined with the help of meticulous descriptions of food and clothing. The book is open-ended enough that sequels are possible, and I think more adventures of Delia Ross would be very fun.

What Wasn't For Me
The opening chapters gave me the impression I was getting into some sort of period buddy comedy, so I was disappointed to find the two leads spent almost no time together at all. Luke Kelly's contribution to the story was not nearly as much as Delia's, and the two only met up briefly from time to time to compare notes.