Veiled in Moonlight — C.J. Archer

When a young gentleman is murdered by a shape shifter, Charlie and Lincoln interrogate their contacts and uncover a plot with links to the royal family -- and links to more than one member of the ministry's committee. At the heart of the mystery is a sinister love triangle, corruption, lies, and treason. As they close in on their suspects, the dangers close in on them, and Lincoln's protective instincts come to the fore, setting Charlie on edge. The last time he worried this much, he sent her away from her home and the people she loved…