Danny believes a serial killer is on the loose when two separate murder victims are identified as members of the same group, charged with a terrible crime.
An investigative journalist refuses to give up a source, even when the source admits to committing murder; Danny works with a troubled teenager as part of a NYPD programme intended to help troubled youth.
Multiple women take credit for murdering the man they worked for. Meanwhile, Frank and his priest clash over how to deal with a boy who has been stealing from the church and Nicky gets into trouble.
Three investigations involve a couple killed in a trailer explosion, a stripper found dead in the worst part of town, and two decomposing corpses in the trunk of a car.
Sherlock offers to help his father with a problem, provided he agrees to leave New York City; Holmes and Watson investigate the deaths of two look-alikes.