From the introduction: FATHOM at its roots is a game about horror, the kind of horror that lurks figuratively deep in the corners of our imaginations, and literally deep underneath the waves. While Fathom’s mechanics can be adapted to any Horror setting, the default setting is one that takes place deep underneath the sea, where things are dark and strange. Think about SOMA, think about Bioshock, think about 20,000 Leagues Under The Sea, think about Cthulhu's Kingdom. You don’t remember much, a few scraps of your past life, a few people. When you woke up in The Complex it felt like you had been dreaming. You weren’t the only one, maybe one of your fellow survivors woke you up, maybe you were the first one to rise and breath in the salt and the grime, like the interior of an ancient tuna can. You learned a few things, about yourselves and about the world. Something had happened and there wasn’t going to be anyone coming for you. They are out there, in the ocean, and you are here protected in your cast iron shell. You all found some preserved food in a storage locker, a few supplies. For those of you who remembered being sailors or pilots it felt like all the things you might need for a crash. This time it wasn’t you that had crashed though, it seemed to be everything else. Those supplies are going to run out soon though, and besides, don’t we want to know more about what happened? There is talk of venturing out of The Complex. Are you going to take the plunge?