It might be called 'The hunt for the bone collector.' This episode had the bone collector polishing bones.
The focus was on another serial killer who was live streaming his murders.
The killings started in Amsterdam some years ago, they have been to several other US cities in the past. Now it is the turn of New York.
The link to the murders seem to be Greek gods and their wrath. The first person killed was narcissistic. By which time the audience would had figured this has gone all Se7en.
The episode was not bad, given that I do not have much hope for this show.
It is derivative with some bad dialogue. Also when chasing a killer who live streams, why do the cops never call for backup?