I do not "believe" in evil in the Judeo-Christian-Islamic sense. I do not believe in it in the Satanic sense. When we talk about evil, in the strict sense in the Western World, I think our reference point (either consciously or unconsciously) is the Devil.
According to this religious mythology Satan turned against God out of sheer willfulness. And we are given to understand that his actions were unprecedented, in that his insubordination seemed to "come out of nowhere."
One of our closest mortal, real equivalents is Adolph Hitler, whom we associate with the concept of actual evil. He was a bad man to be sure. He slaughtered six million Jews to be sure. But he does not meet the Satanic standard as I understand it because his philosophy and methods had a pedigree that dated back centuries or even thousands of years. And so on and so forth. Etc, etc. I've written about it in a hub examining "Free Will Versus Determinism."
But to answer your question: No, I don't believe in "evil" in the Judeo-Islamic-Christian, Satanic sense.