'Sherlock' Season 4 Spoilers: Was Redbeard A Holmes Brother? Tom Hiddleston Guest Starring?

Several "Sherlock" season 4 spoilers have pointed that the New Year special gave some intriguing clues about the appearance of another Holmes brother in future episodes.

Will Tom Hiddleston drop by as the mysterious sibling?

As previously reported, fans have started to speculate on the Redbeard mystery that the special episode seemed to have started.

On the surface, Redbeard is reportedly just a childhood dog which could have died a gruesome death and caused some trauma in the adult Sherlock Holmes (Benedict Cumberbatch)

"Remember Redbeard?" Mycroft previously asked Sherlock in season 3, to which Sherlock replied, "I'm not a child anymore, Mycroft."

Fans on Tumblr speculated that the mysterious Redbeard could actually be a third Holmes sibling. Although the brothers never talked about an addition genius Holmes sibling, followers seem to think that he was "the other one" that Mycroft (Mark Gatiss) asked Sherlock about when he came out of his drug-induced trance.

According to Crossmap's "Sherlock" season 4 spoilers, there's a high probability of another Holmes sibling coming out of the dark.

There have also been talks that this mysterious man, named Sherrinford, will be played by a gifted actor who also happens to be a friend of Cumberbatch.

Will Tom Hiddleston join filming for the series as the other one?

Should Tom Hiddleston join the cast of the BBC drama, this would be the second time that the friends will be working on a project. They were co-stars for the 2011 "War Horse" and remained friends until then.

On the other hand, filming for the fourth season hasn't begun. Executive producer Steven Moffat previously shared that filming will start sometime in April.

Other "Sherlock" season 4 rumors include Mary Watson's (Abigail Abbington) alleged death after giving birth to her baby with John Watson (Martin Freeman).

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