I love the setting of the Shetland Islands for this series and the "simmer dim" or white nights of summer were very evocative for someone who hasn't experienced near-constant daylight. This one also focuses more on Perez's personal life and his developing relationship with Fran so that was satisfying in a way the first book wasn't...there is also a similar denouement of the killer so I'm guessing that will continue into the other books which I found odd--it works the first time because it's unexpected.