Quite a change of pace for me this one.
From the Blurb:
Summons to a bullet-riddled body in a Hell’s Kitchen apartment marks the start of a new case for consulting detectives Sherlock Holmes and Joan Watson. The victim is a subway train driver with a hidden stash of money and a strange Colombian connection, but why would someone kill him and leave a fortune behind?
The search for the truth will lead the sleuths deep into the hidden underground tunnels beneath New York City, where answers—and more bodies—may well await them...