According to Digital Spy, Enola Holmes 3 is currently in production in the United Kingdom, with Millie Bobby Brown back in the titular role. Meanwhile, it remains unclear if previous cast members like Henry Cavill (Sherlock Holmes), Helena Bonham Carter (Eudoria Holmes), and Susan Wokoma (Edith) will return. However, they are all expected to reprise their roles, especially given the popularity and success of the franchise. Behind the scenes, Enola Holmes 3 sees a major creative shift as Adolescence director Philip Barantini handles directing duties after Harry Bradbeer helmed the first two installments. With Adolescence receiving massive praise after a record-breaking debut on Netflix, Barantini has a chance to put his own spin on the Enola Holmes franchise.

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She makes some valid points.
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“I’m going to be doing an ‘Enola Holmes 3’ this year. We start filming in the coming weeks. I’m very excited!”
Is an ‘Enola Holmes’ Spin-Off in the Works?

As of this writing, the Enola Holmes franchise will remain centered on Millie Bobby Brown’s detective. Although Henry Cavill remains an important part of the overarching story as her brother, Sherlock, it certainly seems like he won’t be getting a spin-off anytime soon. In fact, Cavill stated as much during an interview for the second film. Despite Enola Holmes 2 teasing the iconic Sherlock-Dr. Watson duo in a post-credits stinger, the actor does not think a new project following the classic detectives is necessary.
“I think ‘How is there hope for him?’ would be answered in any future movies were they to happen. There’s always whisperings of these sort of things, but nothing is ever official until you enter the first day of shooting, and even then until you finish shooting and even then it has to come out. Right now that’s a that’s all always brings but I don’t know of anything official just yet. The universe is very much Enola’s and she’ll always be involved. I think it’s important to make that connection between the two characters.”