A rare, original copy of the first game developed by the legendary husband and wife team of Ken and Roberta Williams has just hit eBay, and despite being little more than a floppy disk and a slip of paper inside a plastic bag, it's already set to fetch thousands of dollars after just one day on the auction site.
The Williamses are best known as the founders of On-Line Systems, which would become Sierra On-Line, and the creators of the King's Quest series. But On-Line Systems was originally intended to be a business software company, and it's only after Roberta got obsessed with the adventure game Colossal Cave Adventure that they decided to make a game.
That game was called Mystery House, and it's about as indie an indie game as you could have in 1980. Roberta handled the writing and design, while Ken did the programming, collaborating to create a murder mystery where the bodies piled up faster than a slasher flick. It was one of the first graphical adventure games and one of the first horror games, in both cases predating the very terms we use to describe those genres.
The first run of Mystery House was sold through mail-order ads in various computer magazines, and proved successful enough to sell 10,000 copies - which Roberta personally printed and packed into Ziploc bags. On-Line Systems would later reprint Mystery House with more formal packaging, and while all versions of the game are pretty rare, the original version is downright legendary.
All this is preamble to explain just how wild it is that a copy of Mystery House in its original form has shown up on eBay, as Digital Eclipse's Chris Kohler has noted on Bluesky. "Roberta Williams probably bought that baggie at the supermarket and put that sticker on at her kitchen table, is what I'm saying," Kohler jokes.
Later printings of Mystery House already go anywhere from a few hundred dollars to a couple of thousand on eBay, but just one day after posting this original copy has already eclipsed $4,000. And with six more days left to go, it's likely to go a whole lot higher. "I don't think I touched it for 40 years before I unearthed it from a box of old software this week," the seller says, but remarkably they claim that the disk remains in working condition after all these years.
"Man, if I had any idea what kind of price this might go for, I would have tried to clean it up a little more, but I guess you have seen it now," the seller says in a recent addendum to the post.
There's clearly interest in this early edition of Mystery House, but collectors are going to have to be cautious. Back in 2022, there was a notable scandal in the PC game collecting scene when a number of titles - including Ultimate predecessor Akalabeth and a Japanese copy of Mystery House - were discovered to be likely counterfeits. Our friends at PC Gamer reported on it at the time, and it's a notable warning about just how hard it can be to detect a fake PC game of this vintage.
I certainly don't have the budget to be bidding on a game like this either way, but I've got my fingers crossed that this Mystery House listing is legit. It's such a cool item that I need this story to have a happy ending.
Ken and Roberta got back into game development to remake Colossal Cave Adventure.