Gallows Iron: Book Four of the Tyler May series

The balance of the world is shifting. Once an infrequent and disbelieved phenomenon, ghosts are now a fact of life and dark forces are using them.
When MI6 agents get a lead on one of the ghostly gloves, Chapman wants his ghost-haunting spy on the case.
Tyler, Melissa and Lucy are sent on a deadly mission and discover a secret that could make or break the allies' chances of victory.

Contains some violence.