Idea I had for a Call of Cthulhu scenario involving Deep Ones

If your players aren't scared of deep ones you aren't running this right. Deep ones aren't dumb animals or savage brutes. They're intelligent and have access to sorceries and sciences that humans can only dream of. They're also an ancient race on the verge of extinction and getting desperate. One scenario I'm going to run for Call of Cthulhu is what I call the Clinic of the Drowned. The players were terminally ill patients in the postwar 1940s who're receiving miraculous treatment at the Marsh Memorial clinic. Tumors disappear, neural degeneration reverses itself, and decayed flesh springs back to life and health. The strange bug-eyed doctors are insistent on everyone talking their pills, however. Patients who leave always seem troubled as if they've been told a horrible truth, and a few have needed to be institutionalized. If the players break into the mental ward they discover a perfectly ordinary mental hospital. Better actually. This place has won awards for patient care. There isn't anything strange going on in the mental ward.

     When the players get into the basement what they discover is a massive tank of fish flesh tended by strange fishman scientists. After they've been restrained and stopped screaming a deep one with gold-rimmed coral encrusted spectacles explains that they've been implanted with healthy regenerative cell culture harvested from Dagon's bone marrow. The pills are to prevent their full transformation and will be cut off if they tell anyone about this. As for why they're doing this "Humans fear death more than anything. As the years pass you will voluntarily forsake the weakness of prairie ape meat for the eternal strength and youth of the Ocean folk's flesh. The final pill bottle will sit unopened and you will join us beneath the waves to dance in splendour and joy forevermore. Our race will rise again, and the towers of Ghudigbx will above the ocean and make the cities of New Yahk and San France-Sisko seem as the mud huts of the Etruscans."