How did Magnussen know about Redbeard?
In Sherlock, Magnussen whispers to Sherlock Redbeard. So how could he know about Redbeard? Sherlock couldn't tell him because he isn't so stupid. Mycroft won't obviously tell him. So how did Magnussen know about a story so old and so small about 'Redbeard'?
Best Answer
There is no logical explanation that we are aware of. It's likely just a plot seed inserted by the creators of the series (out of universe).
In Universe
Sherlock himself isn't really aware, at this point, of the significance of Redbeard (he still thinks it's a dog).
It seems unlikely that Magnussen is aware of Eurus at this point either as her name does not appear under the list of pressure points applicable to Sherlock.
What DOES appear is the name Jim Moriarty who we know HAS been in contact with Eurus so it's conceivable that Magnussen somehow obtained information (but not all) from him.
PRESSURE POINT:
IRENE ADLER (SEE FILE)
JIM MORIARTY (SEE FILE)
REDBEARD (SEE FILE)
HOUNDS OF THE BASKERVILLE
OPIUM
JOHN WATSON
Pictures about "How did Magnussen know about Redbeard?"
Why did Sherlock think Redbeard was a dog?
Why did Sherlock always remember Redbeard as a dog, not a boy? To protect himself. He rewrote his memory to forget Eurus and to believe that Redbeard was a dog because the truth was far too terrible for him to stand. Still, the event changed Sherlock.Do you remember Redbeard Sherlock?
\u201cDo you remember Redbeard?\u201d The moment: In \u201cThe Sign of Three\u201d, Sherlock rings Mycroft to see if he can make him come to John and Mary's wedding. At the end of the phone call, Mycroft mysteriously asks Sherlock: \u201cDo you remember Redbeard?\u201d Sherlock becomes angry and says \u201cI'm not a child anymore, Mycroft!\u201dWho kills Magnussen?
Using a ruse, Sherlock exposes Mary's secret life as an assassin to John, and all three return to Baker Street to talk it out. She tells them about her past and that Magnussen has information to jeopardize her life. Sherlock deduces that she intentionally shot him in a non-lethal spot and called an ambulance.Figuring out a Fake Painting in just 10 Seconds - Sherlock
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Images: Miguel Á. Padriñán, Ron Lach, RODNAE Productions, RODNAE Productions