Enjoyed the previous seasons a lot but this 2017 4th season has strained trying to outdo itself and has reached a point of ridiculousness that has left me impatient and constantly punctures the suspension of disbelief it takes for the audience to go with the story. There's little consistency shown in the surprise character of the season who shows up at the end of The Lying Detective and takes over in The Final Problem like a computer hacker taking control of the characters and the dynamics between them to which we have become attached and enjoyed so much. I think it was a mistake trying to be edgier, bombastic and to rely so much on action, effects and novelty.

Character in this series and in the Conan Doyle originals was always the keystone. Explosions and special effects are a dilution and a distraction from the heart of the thing.

A disappointing wrap up to an enjoyable concept generally well conceived and effectively realized in the first three series.