Although the accent of course is on our protagonist Sherlock Holmes ferreting out a solution to a murder, in this particular story Sir Arthur Conan Doyle was years ahead of his time in using as a subject a battered wife of the Victorian Era. Options for battered women were quite a bit more limited than they are today.
For reasons he's not quite clear himself about, Scotland Yard's Inspector Hopkins (Paul Williamson) calls in Jeremy Brett and Edward Hardwicke (Holmes and Watson) in on what looks like a break-in robbery of a Victorian mansion gone wrong right into a homicide. Perhaps because the victim was a titled individual and a rich one, Scotland Yard wanted to be sure.
Of course Holmes deduces it was not a break-in gone bad which left the man murdered and his much younger wife tied up. Rather quickly Brett says that Anne-Louise Lambert was the victim of long time abuse. And he also figures out that a sailor is somehow involved in this affair.
What to do about it, well all I can say is that Agatha Christie might have taken a bit from Conan Doyle when she wrote Murder On The Orient Express with her solution for Hercule Poirot when he found the murder.
As Arthur Conan Doyle was an observer of Victorian society, I believe that his victim/villain Lord Eustace Brackenstall may very well have been modeled on the Marquis of Queensbury who later made life miserable for Oscar Wilde. Queensbury had the same kind of temperament that Brackenstall displays and he certainly abused his family. Conrad Phillips plays Brackenstall with relish.
Good Holmes story and dramatization of same.