in this quote "the news stirs up something infinitely black and evil in the town" what does it mean?

'infinitely black and evil,' would mean just that...... in this context the author is referring to the actions of others in regards to the pearl. Money, treasure, and valuables bring out the absolute worst in people; they turn ordinary people into greedy devils...... they can even cause the most sane person to lose their head...... people's lives become as nothing.