In a far distant future, a psionic hormone was discovered in the human brain, granting people extrasensory powers and changing the world as people know it. Just as the humanity was entering this new era, the deranged mutants known as Others began to descend from the sky with a thirst for human brains. Highly resistant to the conventional attack methods, extreme measures needed to be taken to battle the overwhelming threat and preserve the humanity. Those with acute extrasensory abilities, known as psionics, were the chance to fight the onslaught from above. To this day, the psionics have been scouted for their talents and recruited to the Other Suppression Force (OSF), humanity's last line of defense.