'Sherlock' Stars, Writers Discuss Season 4 Opener

The cast and writers talk about the start of the hit drama's new three-part season — with spoilers, for those who haven't watched.

The fourth season of Sherlock, starring Benedict Cumberbatch, Martin Freeman and Amanda Abbington, had an emotional first episode on BBC One in the U.K. and on PBS in the U.S. on Sunday.

The cast and writers discussed the episode at a reception and preview screening before the holidays in London, hosted by BBC director general Tony Hall, with comments embargoed until after the air date.

Written by creators Steven Moffat and Mark Gatiss and inspired by the works of Sir Arthur Conan Doyle, the new season begins with Sherlock Holmes (Cumberbatch) back on British soil as Dr. John Watson (Freeman) and his wife, Mary (Freeman's former real-life partner Abbington), prepare for their biggest-ever challenge: becoming parents.

But the season opener — spoiler alert — culminates in a dramatic and emotional scene, in which Mary dies. "It was good fun, what with these guys," Abbington said in describing the acting experience, gesturing toward Freeman and Cumberbatch. "It’s a dream for an actor. It’s complete self-indulgence. I can just go to town on it. I probably did a bit."

"How challenging is it to play a scene like that?" Freeman was asked. "It’s difficult," he said, before joking, "I’m always on the verge of acting badly. So you have to work up to [the] moment." He concluded: “You have to do it justice, obviously, but it is very easy to overdo it. It is a careful line to walk.”

Cumberbatch agreed that it "really was" a difficult scene. "We get the hit that the audience hopefully gets when they watch it when we first read it. It is a big moment. Two became three, and then this incredibly important part of what Sherlock is is suddenly no more," he explained. “It was a very upsetting scene to film.”

When was Abbington told that her character would die? She said she knew that the character dies in the books, but she found out that the first episode of the new season was the time to say her onscreen farewells when Moffat told her. "And [he] said it would either be something like that [scene that ended up in the episode] or being hit by a bus," she recalled.

Moffat acknowledged: “We did an early road map without any details.” And he explained: “In the original stories, it’s not actually said that she’s died. It’s heavily inferred, but it could be a messy breakup. We have obviously been very true to Doyle and also very untrue. So, we didn’t necessarily have to do this, but it just felt like absolutely the right place to do it.”

He said he wanted to tell the story of Mary's death earlier rather than later, “so that it would happen as wrenchingly and as horrifically as such things happen in real life.”

Asked what the death means for Holmes, Cumberbatch said: "He is becoming, I think, slightly more responsible for his actions. ... That friendship [with Watson], that partnership in crime has been a humanizing element all the way through the series. And I think he is very much now becoming more of a human being ... [and] letting go of ... this sort of very cold results-at-all-costs, it’s all about the endgame rather than the methodology to get there and the people he tramples over."

Discussing Holmes' role in the death, the star added: "Because he is so loyal to someone he cares about, because he has let care in … he has blindsided himself with his own humanity. He becomes so impassionated in his destruction of this [person threatening Mary] in that moment that she becomes weaponized by his cruelty."

Freeman, meanwhile, discussed a new side of Watson shown in the first episode of the new season when he encounters a woman who seems interested in him on the bus. "There is a lot of talk, and understandable talk, of John as this reliable, very steadfast character, which he is, generally speaking," he said. "But he is someone who also has weaknesses and can be at fault at times."

Cumberbatch said that was in line with the Doyle stories. "He is a ladies’ man in the original stories," he said of Watson.

And Gatiss explained that the scene was based on the experience of "a friend of mine, amazingly called Edmund Moriarty," like the surname of the criminal mastermind in the Holmes stories. He was on the subway with his young daughter once, and a young woman smiled at him. “And then he looked in the mirror, and he had a flower in his hair, and that’s what she had been looking at,” explained Gatiss.

Moffat was asked about the creators' past comments stating season four of Sherlock would be the darkest so far. Can it get any darker than the first episode? "Yes, not in an entirely unfunny way," he said. "It darkens considerably."