SERIOUSLY. If you haven't watched the first new episode of Sherlock yet, do not scroll down. DO NOT.
NO SERIOUSLY. SPOILERS.
In a dramatic twist at the end of "The Six Thatchers", Mary (Amanda Abbington) dies after she is shot.
Benedict Cumberbatch said that the sequence was a difficult and emotional moment to film.
For Freeman, his biggest concern was overacting Watson's grief: "You have to do it justice obviously, but it's very easy to overdo it."
Mary's death scene takes place in an aquarium, and Abbington said that to lighten the mood during filming, the people on set would all recite fake shark facts to one another.
Sherlock creator Steven Moffat explained that Mary's death was inspired by the books written by Arthur Conan Doyle.
When asked why they decided to kill Mary off now, rather than during the finale, "The Final Problem", in two weeks' time, Moffat shot back: "Why would that be better? The truth is, Mary has been dead for 100 years so it's harder to surprise people in those circumstances."
He also noted the flip between Sherlock being shot by Mary in "His Last Vow" and Sherlock aiding Mary after she is shot in "The Six Thatchers".
There's also the added issue of Watson getting a number from a stranger earlier in the episode. When asked about it, Freeman said: "It's always interesting to play shades of people."