Only Maddie could go to Hawaii and stumble on a murder mystery. I was a little disappointed that the twins didn't appear aside from mentions. I understood it when Ramirez was back home in LA but when he showed up I expected him to bring them with. It might not have been a big deal, but you'd expect the twins to play a bigger role in the books then they do. I get that we only see Maddie when she's about to stumble upon a dead body (somehow) but she is the mother of twins: you'd think they'd show up more.
Aside from that, this book is pretty standard for this series: Maddie finds a body and Ramirez tells her to stay out of it and she doesn't (you'd think he'd know better by now!), catching the killer and managing to almost get killed herself. The setting is different, but Maddie doesn't really go anywhere in Hawaii but the beach and the hotel.