What is it?

Call of Cthulhu (CoC) is a Lovecraftian horror mystery role-playing game based on the works of H.P. Lovecraft, and the greater Cthulhu Mythos (Derleth’s works and beyond). It has been published since 1981 by Chaosium, and is now up to its 7th Edition.

In CoC, players take on the role of Investigators – everyday people who are more often than not thrust into mind-rending events and terrible truths that threaten to destroy their psyches, and the world at large. Sinister cults, impossible creatures, and unfathomable gods are the most common threats that the Investigators must deal with – and to combat them: they must utilize a set of skills unique to their character.

Art by Victor Leza.

The Game System

Call of Cthulhu is built upon the Basic Role-Playing System (BRP), an incredibly simple and fast-paced system that is focused on skills and character development.

It uses a percentile dice (D100) to determine successes and failures, the higher your skill, the more likely you are to succeed it.

Example: If you have 70 in the Spot Hidden skill, you always have a 70% chance to succeed the roll.

You must work together with the skills your Investigator and fellow peers have to solve strange mysteries, evade creatures that’d bring assured death, and escape with your life and a frayed mind.


One of the coolest things with Call of Cthulhu is its abundance of settings. Being set in a world with history parallel to our own, many of the scenarios published can take place in all kinds of time periods and places.

The most common setting for CoC is the 1920s, the time of jazz, flapper girls, speakeasies, and the economic boom period of a post-Great War United States.

Beyond that, Chaosium has recently published official setting supplements for the Dark Ages (think Vikings and Normans), the Wild West, the Modern Era (1980s-present), and Pulp (a massive supplement full of rules and tone changes that make your scenarios more bombastic).

Chaosium has also made in-depth supplements into certain geographical locations. Like Harlem, Australia, and Berlin so far – all set in the 1920s.

Here’s a list of setting supplements that I recommend:

  • Berlin, the Wicked City – A sensational overview of 1920s Berlin. It provides a guide to establishing a Berlin-based campaign, with the potential of incorporating unique organisations, personalities, and detailed culture. Includes three scenarios.
  • Cthulhu Dark Ages 3rd Ed. – Includes a player’s guide to the Dark Ages, a grimoire of additional spells, a bestiary of new creatures, and a detailed setting of the Anglo-Saxon history and culture. Includes three scenarios.
  • Down Darker Trails – Welcome to the Weird West! Includes the means to create Wild West investigators, new occupations, new mechanics, and more. Comes with two introductory-level scenarios.
  • Harlem Unbound – An overview on the unique location of Harlem during the 1920s. Includes an in-depth setting, seven scenarios, a bestiary of new entities, and a crash course on addressing race in gaming.
  • Pulp Cthulhu – A game of two-fisted action! An entirely new rule-set that will make your investigators stronger than ever, ready to wage war against eldritch horrors. Includes the setting of ‘Pulps’ and 1930s United States; a collection of pulp villains, monsters, and organisations. Comes with four scenarios.
  • Terror Australis 2nd Ed. – An overview of Australian history and geography, followed by in-depth looks at cities, the Australian mythos, a way to incorporate ‘the Dreaming’, and so on. Includes two large scenarios.

Where do I start?

The Call of Cthulhu Starter Set is the way to go nowadays, presenting a quick-start rules booklet that breaks down the game system into its most basic form. Included is a dice set, maps, handouts, investigator sheets, and 3 scenarios that you can play with up to 4 players: Paper Chase, Edge of Darkness, and Dead Man Stomp.

If you have no one to play with, you can try out the Alone Against… series, a ‘choose-your-own-adventure’ style set of books that use the system. Alone Against the Flames is the first of the series, and is included in the Starter Set.

After running through these scenarios, you should purchase the Call of Cthulhu Slipcase Set, which includes the Keeper Rulebook, the Investigator Handbook, and a Keeper Screen Pack, all are essential for getting into the nitty-gritty of this wonderful game. Included are two scenarios that should keep your group entertained for some time.

Finally, Doors to Darkness is a compilation of five scenarios for novice Keepers (Game Masters) that are full of quality handouts and interesting stories. Past this, the Call of Cthulhu range is for you to peruse.

Art by David Ardila.

Listen to these podcasts!

Pretending to be People: An actual-play (Pulp) Call of Cthulhu-DELTA GREEN hybrid podcast. Enter the zany minds of Zach, Thomas, Luke, and Joe in their own unique campaign based in the strange town of Contention and beyond. Expect lots of comedy, exciting character development, and loads of horror!
How We Roll: A UK/Ireland-based actual-play podcast for Call of Cthulhu. It would appear they’ve done almost everything under the sun in terms of CoC scenarios. Each episode is professionally introduced, with years of experience under each player’s belt. I particularly recommend the Two-Headed Serpent campaign.
The Good Friends of Jackson Elias: A discussion podcast hosted by the Call of Cthulhu greats: M. Sanderson, P. Fricker, and S. Dorward. The main topic of discussion is Call of Cthulhu, though they also talk about horror films, weird fictions, other games, and general inspiration. Any enterprising GM should give them a listen.


[UNDER REVIEW] Beyond the Mountains of Madness – An epic ’30s campaign that acts as an sequel for H.P. Lovecraft’s At the Mountains of Madness. Best suited for roleplay-focused players with survival horror preferences.

Forget Me Not – A Modern Era scenario that is best run as a one-shot for mature players, starting in media res for your unfortunate Investigators.


Beyond the Mountains of Madness – Available only to my players, as requested.


[PLANNING] Only Yourself: A compilation of 4 short scenarios designed for 1-on-1 play. Each scenario is set in a different era, all with a similar theme.

Header image by Sam Lamont, for the Keeper’s Rulebook 7th Ed. cover.

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