The death of Inspector Durban in The Shifting Tide leads William Monk to replace Durban with the Thames River Police as a debt of honor and to provide some much-needed income. As the book opens, Monk is shivering in the bow of a police boat during January as the boat slowly approaches Waterloo Bridge. Less than two hundred feet away, Monk spots a man and woman facing one another with passion . . . just before something terrible happens.
The unexpected event places Monk into an investigation that the Thames River Police would normally not pursue, much to the consternation of his new supervisor who is rightly concerned about a surge in river robberies. At the same time, Monk is having a hard time gaining control over his men and learning how to stop river crime.
As Monk pursues his investigation, he finds lots of loose ends that leave him dissatisfied. That, in turn, leads him to an uneasy alliance with his former friend and adversary, Superintendent Runcorn.
The loose ends all tie together into a trail that leads to the mad dash to create sewers to eliminate disease from London. Before the book ends, both Monk and Hester find themselves among the dank, dark underground rivers that criss-cross London. You'll find as entertaining a crew of expert underground helpers as Charles Dickens ever produced for these adventures.
I was tempted to grade this as a five-star book, but I couldn't quite bring myself to do that after remembering how slowly the book develops after the initial scene. Certainly, from about the half-way point to the end, this is a five-star effort full of interesting plots, subplots and villains that you'll long remember.
I don't recall a book in this series that I've enjoyed more than the second half of Dark Assassin.
The unique nature of river crime promises more exciting stories to come in this fine series.