"The Maniac Mansion series of games deals with the weird events happening at a Victorian-era mansion, inhabbited by the strange Edison family. The events taking place at the mansion thus far have dealt with college kids exploring it's strange mysteriesm and has even changed history as we know it.
Perhaps one of the weirdest characters inhabbiting the mansion is the infamous Purple Tentacle, a maniacal genius intent on taking over the world for his own devilish plans.
It has been twenty years, to the day, since a mysterious purple meteor came hurtling out of the sky and made a large crater in the front lawn of a huge Victorian-era mansion belonging to the Edison family. Dr. Fred, his wife Nurse Edna, and their son Edward "Weird Ed" Edison were reclusive people who left the house very rarely, but the meteor's arrival brought about a strange change in Dr. Fred and the family were seen even less, and even their mansion has fallen into disrepair. Lately, patients from the local hospital have begun to disappear without trace."
Source: Wikipedia, "Maniac_mansion", available under the CC-BY-SA License.