Bram Stoker's Dracula
Johnathan Harker, a solicitor (i.e., lawyer), traveled to the Carpathian Mountains in Transylvania to meet with Count Dracula, a wealthy, landowning gentleman of very old lineage. Dracula was interested in moving to England, and needed representation for the sake of purchasing land and gaining ownership (apparently wanting to move about the world legitimately, not through a quest to just kill every human and own the land as the last man standing -- so, see, he's growing as a person). Harker was to aid the Count, finalizing the paperwork and smoothing over matters.
As it turned out, Harker was in for quite a surprise: the Count was a vampire, and as soon as Harker's legal job was completed, and the paperwork was sent, Harker was of no more use to the Count except as a source of blood. The Count left Harker to the Brides (the vampire women controlled by Dracula -- presumably because he was more powerful than they were), while the Count traveled by ship to Whitby, England.
The ship the count hired ran aground in Whitby, with all crew dead or missing. The ship's log detailed a horror story of disappearing crew, a horrible curse, and a spectral wolf attacking the men. Unrelated to these events (of course, because to think otherwise would be silly), the Count has set up shop in his new digs, unperturbed by the events of the ship crash.
It's not long before a strange illness starts spreading across the countryside, though. Lucy Westenra, friend of Johnathan Harker's fiance, Mina Murray, falls ill, seemingly from anemia. When a creepy old doctor (and friend of one of Lucy's suitors, Dr. John Seward), Van Helsing, comes a-calling, though, he proclaims it's "the work of vampires!" (presumably while clutching a cross to his chest and giving his best "crazy eyes"). They are unable to save Lucy, but when Mina, too, falls under the "disease", the hell-fiend has to be found.
Soon enough, suspicions fall on Dracula (just because he's dashingly handsome and never goes out at night, plus there's that whole having no alibi and not casting reflections thing, which is a total give-away as far as we at the Inverted Dungeon are concerned). Dracula flees back to Romania while the men-folk of London (the late Lucy's suitors, including American cowboy Quincy Morris, plus Van Helsing) give chase, leading to a confrontation at Dracula's own castle. The Brides of Dracula are dispatched. Dracula is lured out, and then killed. Mina is freed, and everyone who isn't an unassuming vampire (or already dead) lives happily ever after.
In 1994, Konami decided to link the Castlevania series to Bram Stoker's original book, Dracula. The series already had a solid connection to the various cinematic works spawned by Dracula and its ilk, and since Dracula was the lead antagonist of the series, a more solidly set up literary connection actually made a certain amount of sense.
The next official, chronological game in the series, Castlevania Bloodlines, established the direct connection. In that game, the backstory for hero John Morris states that he is actually the son of Quincy Morris (suitor of Lucy, as covered above). Quincy dies at the end of the book (and the start of the game), but it's declared that Johnny boy was there (at the age of three, apparently) and saw the whole thing. This inspired him to pick up the family whip (the Vampire Killer, implying that the Morris clan is an American offshoot of the Belmont clan), and eventually take on Dracula himself.
Now, far be it from us to tell Konami how to write their games (our story submissions keep coming back with rejection notices), but it's unlikely that a three-year-old kid -- or really any kid -- would have been taken on a last-ditch, cross-continent excursion to defeat Dracula. Beyond which, John never shows up in the book, and it's never explained, if Quincy was in Europe looking for a new bride, why did he have his kid with him? "I know it's the early 1900s, and people are so very proper all over the globe, but here's my kid and will you marry me?"