"[Episode 3] is the culmination of everything we’ve building up for for the past 6 years of Sherlock,..."

“[Episode 3] is the culmination of everything we’ve building up for for the past 6 years of Sherlock, all kinds of clues and red herrings are finally paid off in episode three, which features…lots of extraordinary things I can’t tell you anything about, and possibly things will never be the same again.”

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Mark Gatiss, Sherlock Series 4 Preview (x)

TFP was bad enough without having been expecting the world based on what Gatiss had said about it. Like… in what reality is the psychotic sister episode the culmination of everything? There was any true character development in it.