City of Ghosts Series Collection 3 Books Set By Victoria Schwab (City of Ghosts, Tunnel of Bones, Bridge of Souls):

City of Ghosts:
Ever since Cass almost drowned (okay, she did drown, but she doesn't like to think about it), she can pull back the Veil that separates the living from the dead . . . and enter the world of spirits. Her best friend is even a ghost. So things are already pretty strange. But they're about to get much stranger. When Cass's parents start hosting a TV show about the world's most haunted places, the family heads off to Edinburgh, Scotland.

Tunnel of Bones:
Trouble is haunting Cassidy Blake . . . even more than usual.She (plus her ghost best friend, Jacob, of course) are in Paris, where Cass's parents are filming their TV show about the world's most haunted cities. Sure, it's fun eating croissants and seeing the Eiffel Tower, but there's true ghostly danger lurking beneath Paris, in the creepy underground Catacombs.

Bridge of Souls:
Cass might have this ghost hunting thing down. After all, she and her ghost best friend Jacob have survived two haunted cities while travelling for her parents' TV show.But nothing can prepare Cass for New Orleans, a city bursting with old magic, secret societies, and scary séances. And the biggest surprise? An enemy she never expected to face: a messenger of Death itself.