Delivering Death (Riley Spartz #6) by Julie Kramer (Atria/Emily Bestler Books hardcover, 7 January 2014).
Minneapolis television reporter Riley Spartz finds a package in her mailbox at work, and upon opening it, is taken aback to find 27 teeth. Stinky, bloody, gross teeth. She takes them to her dentist, who confirms that they are human teeth, after eliciting a promise to come in for a checkup.
Riley gives the teeth to the police and continues with other investigations while she waits for a report, but learning who the teeth belonged to and why they were sent to her is still her personal priority.
Her search leads her all over the state. She even turns to her ex-fiancé Nick Garrett when another story sends her to the Mall of America where he is the director of security.
One of the coolest things about Riley is that she has a life outside the newsroom. Yes, investigating news stories is her main focus, but she goes to her high school reunion, visits her parents, and worries about her love life. The latter is especially on her mind because her boss wants her to cover a group wedding at the Mall.
All this leads to a well-developed character, with a story that is exciting and gripping, and may cause readers to stay up way too late (so don't start it before bed).
It's not necessary to have read the previous books in the series, to understand this one. But if you haven't, Riley is such a fascinating character, you'll probably want to know more about her.
FTC Full Disclosure: Many thanks to Edelweiss and the publisher for the e-galley.