Benedict has known Una Stubbs (Mrs. Hudson) his entire life because she is a close friend of his mother. So the affection Sherlock shows Mrs. H is completely real and completely Benedict's doing (Moffat didn't write it in initially). << that is precious!!!!
SHERLOCK (BBC/PBS) ~ Benedict Cumberbatch as Sherlock Holmes behind the scenes during the filming of the pre-Season 4 special, SHERLOCK: THE ABOMINABLE BRIDE, which premieres January 1, 2016 on BBC and PBS.
What’s it like with [the boys] on set? Are they naughty? Do you keep them in line? "Completely naughty. And they love shocking me, but it doesn’t shock me. They’ve forgotten I was in the Folies Bergère, I was a chorus girl for years—I’m not a nun."