"You have to see the three stories to understand what I originally said, which was it feels like..."

“You have to see the three stories to understand what I originally said, which was it feels like something comes to a head in this series, and that’s not just, you know, false advertising–it’s true to what happens in the stories. So let’s leave it at that. Let’s see how people react to where we go with it, and, you know, as we always do say, we never say never. We didn’t know we were going to get a fourth series, so here we are. So, you know, watch this space. Don’t give up hope, but just enjoy what’s coming rather than worrying about what might or might not be coming in the future.”

- Benedict Cumberbatch on BBC Radio 5 Live, 19 December 2016 (x)