For me, this was my first exposure to Call of Cthulhu. I received it as a Christmas gift from my parents back when I was in high school in the mid- to late-80s. (Now that I think of it I also once received a complete Edgar Allan Poe collection from my wife - I get some creepy gifts.) This was not my Chaosium RPG now that I think on it - I know I had Ringworld and had also played Elfquest by this point. (Elfquest is another property I'll need to discuss at some point - as I recall it was rather big back in the 80s.)
I really don't know how it was my parents came across this version of Call of Cthulhu - it is my understanding that the 3rd edition was the Games Workshop version and was a UK-based release (though I am pretty certain they bought it from a local Waldenbooks so perhaps it was released in the US as well).
One thing which amazes me is how little the game has changed across editions. I could make a character with this version of the game, published over 25 years ago, and bring him easily into the most recent version of the game. I've also used scenarios from this book for 6th edition Cthulhu games.
Be that as it may, let's take a look at the game on its own merits. It is a hardcover book, a bit longer than a normal US RPG book, with black & white pages with color plates inserted. The book is divided into "sub-books" - basically it's as if the contents of a boxed set were bound up into a hardcover book (though it took me as a new player a little bit of time to figure that out). The "books" contained within are:
- Investigator's Book: Under 30 pages long, contains rules for creating characters, action and skill resolution, sanity rules.
- Keeper's Book: About 50 pages long, rules for the Cthulhu mythos, magic, and introduction on how to run the game. Includes three sample scenarios including the classic "The Haunted House" which has probably begun more Cthulhu campaigns than any other scenario.
- Sourcebook for the 1920s: The 3rd edition generally assumes a 192s setting and these 30-ish pages include information on life in the 1920s.
- Cthulhu Companion: As I recall, this is pretty much the 2nd edition Cthulhu Companion, with information on the Mythos in Mesoamerica, new scenarios, sourcebook additions, etc. For some reason one thing which really stuck with me was a list of prions in the 1920s, with one sounding like it would fit perfectly in the film The Dark Knight Rises.
As far as rules go, not a whole lot has changed between this and the 6th edition. Books are rated on how well they impart new spells, something later dropped form the game, but aside from that the game has changed more in the form of tweaks and clarifications. It still has characteristics rather similar to games like D&D, ranging from 3-18 in most cases. The characteristics don't make a huge difference, though the Education and Intelligence stats do play a large roll in your number of starting skills. The game still uses a simple percentile skill system with no real difficulty system added to it - though every game I've been in has used various modifiers to indicate difficulties when needed. Though I've needed to use that rarely - generally I assume if you need to roll the task by its nature is already difficult.
One thing I think later versions of the game do a little bit better is impart the feel of Lovecradtian horror up front. I think that's mainly due to their inclusion of Lovecraft's tale The Call of Cthulhu. Truth be told I was unfamiliar with Lovecraft when I first got the game. I'd just heard a lot about the game from Dragon magazine and other gamers and was curious. Don't misunderstand me - the game does a good job with its atmosphere, I just think later versions do it better. It becomes very clear from looking at the stats of creatures of the Mythos and the sanity rules of the game that this is not a game where you kill the monsters and take their stuff. You're more likely to blow your own brains out in an attempt to avoid becoming an insane slave of some Mythos creature.
As with all versions of the game I feel one of the best things it has going for it is the inclusion of several scenarios. There are some in this book that to the best of my knowledge have not been reprinted in later versions of the game - though I do lack a copy of the 4th edition. Some of the scenarios are quite unusual. There is one featuring a ghoul whose main objective is getting lots of books for his library. Two other scenarios take place in unusual locations - The Mystery of Loch Feinn taking place in Scotland (and would make for a good Gaslight scenario as well) and one of my favorites, The Secret of Castronegro, taking place in New Mexico. This scenario also fits in well with the Mesoamerican Mythos information found in the Cthulhu Companion book.
Like most Chasosium games, Call of Cthulhu 3rd Edition has a ton of information within it. You could run a very enjoyable campaign with just this book (a fact true of later versions as well). For modern gamers, the rules have changed very little. However, some of the articles and scenarios which seem to have not found their way to later incarnations of the game remain very usable and worthwhile. While there is no digital reprint of this version of the game available you can get a lot of the unique information from the 2nd edition Cthulhu Companion. The 2nd edition rules had been available from RPGNow but looking now it appears they are no longer there.