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You're just an ordinary 1930s inhabitant of the ordinary town of Arkham, Massachusetts—a plain New England place where nothing unusual ever happens. Well, except for that one infestation of hood-wearing cultists hoping to usher an angry Elder God into our world. Or that little problem with the Dark Young of Shub-Niggurath. Or those 17th-century witches who don't seem to be quite dead yet. Or that matter of the snake god Yig.

When occult trouble threatens, Miskatonic University's aging librarian, Professor Henry Armitage—the kind of man who runs a "restricted section" featuring books like the human-skin-covered Necromomicon—beckons you to his office. In his kindly way, he asks if you would be so good as to poke around Arkham, ask some questions, visit a few locations—in other words, clear this whole mystery up. Of course, it's probably nothing...

The cases in Mythos Tales—the main game book has eight—all begin in Armitage's sunny library office, where even the strangest goings-on feel manageable. From there, though, you hit the streets of Arkham alone, where you venture into decidedly un-sunny places like secret societies, the Unvisited Isle, and a building called (with good reason) the Witch House.

Mythos Tales is fully cooperative and works as well with one player as it does with more. On each turn, the team decides—using clues from the case, a map of Arkham, and a telephone directory—which location to visit to next. Every visit advances a time tracker, and the more time you take to solve a case, the lower you score at the end. When visiting a location, you look up the spot in the big "investigation book," read the entry (if one exists), and take notes on what you've learned before deciding where to go next. At any point, you can end the investigation and return to Armitage for a grilling about the case. Every question of his that you can answer correctly is worth points. After that, Armitage explains how he also investigated the case—and usually did so much more quickly than you.

That's the game! Mechanically, it's quite simple—move and read, move and read—but the agency Mythos Tales invests you with is compelling. An entry or two into your first case, you really feel like an occult investigator moving between the sites of sinister rituals and the high society of Arkham. Every case comes with a newspaper for that day, too, adding more flavor to the world (and usually a few clues).

The result is a mystery/horror mashup of detective fiction and a Choose Your Own Adventure book. Yes, if this sounds a lot like the earlier Sherlock Holmes Consulting Detective game, you're not in the Dreamlands; this is largely an identical system, now set in H.P. Lovecraft's Cthulhu mythos. Despite the derivative mechanics and the truly insanity-producing number of typos—something we'll return to in a bit—I had a wonderful time in Arkham.