On a snowy Thursday night in Chicago, there is a knock on Detective Hank Purcell’s door. Sister Mary Philomena has seen something terrible at Saint Fidelis Church — a violation of all she holds sacred.
The next Monday, she is found murdered in the convent basement, next to a furnace stuffed with old papers and photographs.
And Margaret, Hank’s teenage daughter, has disappeared.
Hank and his unconventional partner Marvin Bondarowicz try to force their way through a wall of ecclesiastical silence to find the killer, while their search for Margaret takes them from swank lakeside flats to drug dens to south-side basement blues clubs…and the snow keeps falling.