Sherlock star Andrew Scott has revealed that he knew that Moriarty’s storyline wasn’t over “years ago”.

The actor made a surprise return as Moriarty in the final moments of Series 3’s finale, ‘His Last Vow’, earlier this year.

Series 4 has been confirmed, but it is still uncertain when new episodes will be filmed and broadcast.

Scott told Digital Spy: “It’s just a question of getting everybody together, really. Everybody is super-busy – I wouldn’t like to be the production scheduler on Sherlock! When you’re making essentially three films, it’s difficult to get all that time in.”

Asked if he always knew that Moriarty would be seen again, he commented: “All of our plans on Sherlock are long-term ones, so yeah, I certainly had a feeling that Moriarty’s storyline wasn’t over. And then a little bit nearer the time, Steven [Moffat] and Mark [Gatiss] told me that there was going to be an appearance of sorts in Series 3, so I knew about that stuff years ago. I don’t like to ask too much in advance, so I just went about my business, but I did know that there would be some involvement for Moriarty in Series 3.”

As for whether Moriarty is really back in the last scene of ‘His Last Vow’, the actor teased: “I do know the answer to that question, yes! And I’m not going to tell you.”

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