The Beast by Faye Kellerman

An elderly billionaire is found dead in his apartment--with his pet tiger. But it wasn't the tiger that caused his death. It was a bullet and a bash to the head. Homicide cop Peter Decker and his team are on the case. And when they discover that the tiger was not the only exotic animal on the premises, things take a definite turn for the weird. The Beast also picks up the story of Peter's foster son, brilliant teenage musician Gabe.

It's an interesting story, though at times kind of gory. And I always like checking back in with Peter and his wife Rina, whose life seems to be heading in a totally new direction (literally and figuratively) by the end of the book. But this one moved a little slower than some of the others in the series. However, I will check back in to see what happens next.