As a mystery, it was rather "eh" - but that's not really why people read these books. The real draw of this series is Chet, our faithful canine narrator.
There is something so compelling to dog lover's (like myself) about imagining what a dog's inner voice sounds like. And Spencer Quinn scratches that itch with perfection. Chet is so charming and loyal and goofy and forgetful and well-trained (until he's not) that it's clear that the author has bonded with a dog or two in his lifetime.
Light, humorous, and easy, these are delightful books to pull out at those times when real life has become complicated and stressful.