I actually liked the second storyline more than the first. I think that having the characters fleshed out in the first season enabled more time to the story as well as the deepening relationships between the characters.
If you like detective shows and period pieces you cannot go wrong with this series.
Actually, my only gripe is the whispery way the main characters speak. I don't remember that from the first season and it is an annoying affectation. If it were just one character, fine. But all three main characters speak in a breathless hush. Yes, you can hear their lines but what is the point? Vocal cords are not new discoveries so I am not sure what the actors/directors were going for. Just a pet peeve because otherwise I would recommend the show.
Review of The Alienist
