Holy: Book 4

Sequel to Cumin, Plain, Gang, but can be read on its own. Mai is preoccupied with building relationships with her soon-to-be in-laws, but SPR's ultra ritzy, high profile case in a famous hotel could turn her plans of a wedding into a funeral. No one can be trusted, no one is in the right place at the right time, there's a too easy suicide wandering the halls, and Masako and John are acting dangerously and oddly daring.