Something Strange and Deadly by Susan Dennard
Sixteen-year-old Eleanor Fitt's brother is missing. And when she discovers that the Dead are rising in Philadelphia and wreaking havoc throughout the city, she knows that her brother is involved. So Eleanor enlists the help of the Spirit-Hunters. This motley crew, hired to protect the city from supernatural forces, is after the necromancer who has been reanimating corpses. Their skills can save her brother. But as Eleanor spends time with the Spirit-Hunters, and their handsome inventor, Daniel, the situation becomes dire. Now not only is her reputation at risk, but her very life may hang in the balance.