Tomb of the Queen (Jayne Thorne, CIA Librarian Book 1)

Librarian Jayne Thorne lives a quiet life until she discovers a spell book in the Vanderbilt University archives that grants her access to a magical dimension. Hunted by a magic-wielding terrorist organization, she is forced to join a secret branch of the CIA. Her first assignment takes her undercover to Trinity College Library in Dublin to investigate whether the Book of Leinster is a magical necromantic grimoire. Working with an Irish kickboxer, Jayne learns that the Irish manuscript is one of five grimoires capable of raising five dead master magicians and securing their totems of power. These totems would grant their wielder the ability to control the world. As Jayne navigates her new life, she discovers that danger surrounds her at every turn. She must embrace her unexpected role or risk the world's destruction.