Betrayed (House of Night #2) by P.C. Cast and Kristen Cast
Things in Betrayed pick up almost immediately after the events of Marked. Zoey is becoming accustomed to the powers the goddess Nyx has bestowed upon her, and is the new leader of the Sons and Daughters of Darkness. She’s got a great group of friends and a sort-of boyfriend or two.
But then human teenagers from her old high school start to get killed and signs point to vampires, bringing suspicion on the House of Night. At the same time, Zoey starts getting suspicious about how things work at the House of Night, all while being courted by three different guys. One of these “relationships” is kind of creepy because it’s with an adult but the overall development in Zoey’s personal life is interesting.
There’s a lot of plot advancement in this story and some of the content is pretty heavy. There are some great twists and some of the mysteries from the first book are brought into this story, and expanded. It’s a really great plotline, actually, that strongly advances the story in Betrayed. I’m going through these books pretty quickly so I hope that I’ll be able to read the next book, Chosen, soon.