Guy Ritchie’s Prime Video origin story series Young Sherlock follows a teenage Sherlock Holmes (Hero Fiennes Tiffin) in his pre-detective Oxford University era and introduces his longtime rival James Moriarty (Dónal Finn). We would never know that these two characters were destined to be mortal enemies, as their friendship is really the heart of the first season.

“I had to keep telling myself to forget knowing the inevitable of knowing where their friendship ends up,” Fiennes Tiffin said during their panel at Deadline Contenders TV. “The idea of them initially being friends really enriches the idea of them getting to where they get to.”

Finn had a revelation about Moriarty’s life post-friendship with Sherlock. “How painful a breakup can be, because essentially if they’re best friends, then the idea of them being enemies at a later point in life is only colored more greatly by a sense of personal betrayal,” he said. ‘Especially if these two people are people who might feel like they’re outside of society in a lot of ways or if they take a lot of refuge in their relationship. I think the idea of that trust and closeness you build as friends going wrong for you only solidifies that it’s right to be a lone wolf.”

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The two actors talked about the challenges and benefits of working with legendary director Ritchie, who is known for making changes on the fly. “Guy brings the spontaneity and fun to it,” Fiennes Tiffin said, “so as much as he can give you lots of dialogue or change scenes, weapons two minutes before we shoot, you always rather do what he wants on the day because it’s just always better.”

Season 2 is in the works, and the actors already have received the first couple of scripts. When Fiennes Tiffin was asked to tease what’s coming up next, he said: “I just read Episode 1 and 2 on the plane over here — not many notes. Just really excited. We’re all so chuffed.” Joked Finn: “I’m not reading Episode 1 because I know it will change anyways — it will be a different script on the day.”

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The record-setting Prime video series premiered March 4, reaching 45 million global viewers in under a month and ranking No. 1 in 95 countries. The trailer broke records garnering 223 million views in one single week. 

Check back Monday for the panel video.

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