The series seemed to stumble a bit with the last release, Murder on Waverly Place. This time, the murder mystery is constructed much better, the witty interaction between Frank Malloy and Sarah Brandt (that seemed to be lacking in the last book) is there, and the requisite historical facts-of-the-time are vital parts of the plot(Princeton's re-naming, the eugenics movement, etc.).
Unlike the recent books, which involved more of Sarah's world, this book's mystery is related to something involving Malloy (schools for the deaf- and their varying methods). This book gets to balance the mystery with insights into Malloy--We get to know how grateful he is for Sarah's interference in his life- which has in turn improved his son's quality of life. Since he is no longer hesitant to include and share details of the case with Sarah, and they both get to play key roles in solving the mystery.
There is a delightful scene when Sarah recreates for Frank a bit of sign language for him (which she doesn't know the meaning), but for those longing for Malloy and Sarah to finally acknowledge their feelings, well, the progress remains slow.
It's a breeze of a read, and it will be hard to wait so long for the next installment (the author seems to be setting up the mystery surrounding what happened to Catherine before she came to live with Sarah).