Why does just about everyone in this movie call Arthur Conan Doyle just Mr. Doyle? As I understand it, Conan Doyle is his full surname, so it should be Mr. Conan Doyle.

Very common error. Most libraries have his works listed under DOY, rather than CON in the call numbers. If he'd had the name hyphenated, it probably wouldn't be so confusing. "Conan" sounds like his middle name.

My sister had rented the DVD of From Hell (which is about Jack the Ripper) and we were watching an extra about the Jack the Ripper killings. Among the suspects was Niell Cream, aka the character portrayed by Alec Newman in this story. However, he's one of the less likely possibilities, as he was reported to be in prison over in the States at the time. A theory that it was actually a double in prison seems a bit iffy.