In February of 1880, the whaling ship Hope sailed north from Peterhead, Scotland, and headed for the Arctic. Her crew included a highly regarded captain, an illiterate but gifted first mate, and the usual roster of harpooners, sailors, and able-bodied seamen--but not the intended ship's surgeon. That gentleman having been unexpectedly called away on family matters, a last-minute substitute was found, in the form of a middling third-year medical student making his maiden voyage: a young man by the name of Arthur Conan Doyle. Conan Doyle was twenty when he left Peterhead and twenty-one when he returned. On Saturday, May 22nd, in the meticulous diary he kept during that journey, he wrote, "A heavy swell all day. I came of age today. Rather a funny sort of place to do it in, only 600 miles or so from the North Pole." Funny indeed, for a man who would come to be associated with distinctly un-Arctic environments: the gas-lit glow of Victorian London, the famous chambers at 221B Baker Street, and--further afield, but not much--the gabled manors and foggy moors where Sherlock Holmes tracked bloody footprints and dogs failed to bark in the night. Shortly after returning from the north, and long before writing any of the stories that made him famous, Conan Doyle told two tales about the Arctic--one fictional, the other putatively true. The first, in 1883, was "The Captain of the Pole-Star," one of his earliest published short stories. In it, a young medical student serving as the surgeon on a whaling ship watches, first in disbelief and then in dread, as his captain goes mad. Although winter is closing in, the captain sails northward into the Arctic until his ship is stuck fast.

Life has been busy for the stars of "Sherlock" since the series premiered in 2010, with Steven Moffat and Mark Gatiss applying new London style and contemporary quirks to Arthur Conan Doyle's famous consulting detective. Its fourth season -- there have been breaks -- begins Sunday on PBS' "Masterpiece: Mystery!" Martin Freeman, the series' Dr. John Watson, has gone from a guy you might have seen on the British version of "The Office" or in "The Hitchhiker's Guide to the Galaxy" to playing Bilbo Baggins in three "Hobbit" movies and the hapless Lester Nygaard in the first season of FX's "Fargo," and hosting "Saturday Night Live." Benedict Cumberbatch, its Sherlock (also in the "Hobbit" movies, as the voice of Smaug) has, among other things, played Khan in "Star Trek Into Darkness," the title role in "Doctor Strange," codebreaker Alan Turing in "The Imitation Game" and Richard III in BBC's "The Hollow Crown" Shakespeare cycle; sung "Comfortably Numb" with Pink Floyd's David Gilmour at the Royal Albert Hall; and has become something of an international, official hot guy. Conan Doyle wrote 60 Holmes stories, but the world has deemed that insufficient, and many other hands have filled out the tale. Holmes is a useful mix of specific qualities and scant details -- an attitude, occupation and method as much as a full-fleshed, full-fledged character, and so familiar that even some characters not called Sherlock Holmes, like Hugh Laurie's Dr. House on "House," are recognizably him.

We describe a method for identifying the speakers of quoted speech in natural-language textual stories. We have assembled a corpus of more than 3,000 quotations, whose speakers (if any) are manually identified, from a collection of 19th and 20th century literature by six authors. Using rule-based and statistical learning, our method identifies candidate characters, determines their genders, and attributes each quote to the most likely speaker. We divide the quotes into syntactic classes in order to leverage common discourse patterns, which enable rapid attribution for many quotes. We apply learning algorithms to the remainder and achieve an overall accuracy of 83%.