Although this Adventure Hook is probably more suited to a horror RPG like Call of Cthulhu it could work well within other systems like Savage Worlds (especially Realms of Cthulhu of course) or even Dungeons and Dragons with a few tweaks and the home could easily be fleshed out as a dungeon crawl.
Ian Theobald Orton was a famous adventurer and explorer who made his fortune finding and selling rare artifacts, artwork and curiosities. At least that’s how the story goes in his official biography. The truth however is much less prosaic. Mr. Orton did indeed travel far and wide and dabbled in selling some of the more mundane things which he found in his travels, but his main purpose was the accumulation and use of long-lost forbidden knowledge. A purpose to which he was uniquely suited and at which he greatly excelled.
Towards the end of his life he commissioned and built the Orton Estate on the outskirts of the city. Rumors insist that Orton himself drew up the plans for the home and used different contractors for each stage of the construction so that no one person other than himself knew or fully understood the layout. Many people even say that Ian Orton himself did much of the work even though he was upwards of sixty years old at the time.
Once the home was complete Mr. Orton spent the next few years arriving with trucks full of the art and curios he had obtained throughout his career as well as continuing to do some travel and acquiring more items which interested him until the time of his purported death over seventy-five years ago when ownership and upkeep of the estate passed to a Trust Mr. Orton had set up for the perpetual upkeep of the property for use by his family.
The Hook
Two weeks ago Natasha Hagelman, a seventeen year old local girl, disappeared and was last seen near the Orton Estate. Authorities looking into the 
disappearance have come to the conclusion that the girl must have run away from home and have officially closed the investigation. Natasha’s family however don’t believe this is true. Her father is a long-time resident of the area and remembers several other disappearances around “the old Orton place” over the years and hires the players’ characters to investigate.
The Truth
Although investigations will show that the Orton Estate is currently owned by Ian’s great-grandson Henry Orton the only current resident is Ian himself. Having prolonged his life and become immortal by turning himself into a Ghoul (a ghost or lich would work as well depending on your gaming system) he has continued his research. Even now Ian has an insatiable thirst for forbidden knowledge which leads him to contact creatures from many realms. These entities always require some type of payment for what they know and sometimes that payment comes in the form of humans. When this occurs Ian abducts a passerby near his Estate and trades them for the information he seeks. This has happened eight times in the seventy-five years since his “death” although only six were ever reported locally as the other two were from out-of-town, one a hitch-hiker and the other simply had the misfortune of being stranded near the estate on the wrong night.
