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A photograph of the actor, alongside Amanda Abbington and Mark Gatiss at last weekend's San Diego Comic-Con, has sent fans into hysteria, with many speculating that the heartthrob will
star in the BBC drama. Co-creator Gatiss, who also plays Sherlock's brother Mycroft, captioned the picture "blud", fuelling rumours that the 35-year-old boyfriend of Taylor
Swift will appear as another of the sleuth's siblings. Just hours after the Sherlock cast dropped some tantalising teasers of series four, fans on Twitter went into a meltdown over the
intriguing snap, with one posting: "I swear to god, I will freak if it turns out that Tom Hiddleston's been cast as the third brother. Please God, make this happen." Another
asked: "Does Tom play the long lost Holmes brother?"