Threshold learns that the aliens are attempting to rewrite the DNA of the human race using, in part, an audio signal that somehow alters some people's body chemistry in such a way that they become alien themselves. Central to all this is a fractal triskelion pattern that keeps appearing – in electronic signals, blood, and even the pattern made by city lights. Its significance has yet to be revealed, though Arthur Ramsey interpreted it as representing a DNA pattern in a triple helix formation (like the alien DNA).