This is a classic for good reason. The writing is not overly florid given when and where it was written (late 19th Century Britain). The plot is absolutely ridiculous, but the pace of action will keep you on board with it. The entire story revolves around a plot to dethrone the king of Ruritania (forerunner of Latveria, Elbonia and Kerplakistan) and a lookalike. I’ll say no more as the whole plot hinges on your ignorance of it.