The Disappearance of Lady Frances Carfax - a Sherlock Holmes Short Story

It was an average day at 221B Baker Street when, out of the blue, Sherlock Holmes suggested to Dr. Watson that he, Watson, was in "need of a change." He asked, "How would Lausanne (Switzerland) do, my dear Watson - first-class and all expenses paid on a princely scale?"

Holmes is sending his friend to find Lady Frances Carfax who is missing. She's the last direct descendent of the late Earl of Rufton and was last heard from nearly five weeks ago in Lausanne. Apparently she left her hotel for a location unknown. Can Watson go to the continent and track her down? Of course, readers know there's something a foot but what?