Is evil that powerful?

I have seen hundred of horror and other movies and usually we see in horror movies that evil is hard to finish off. By the look of numerous movies based on evil character, they keep on giving us sequel after sequel and even if those evil characters are shot, hacked to death or try to kill in any number of ways, they keep on living. I know it is the movies but that is what the film makers think that evil will not die. But is evil that powerful that you cannot kill it eventually? I know that as long as this world remains there is always going to be a battle between good and evil and it sometimes seems that evil does win in some cases. The only way that evil can be defeated is self control. There is no other way to defeat evil in my opinion. If you have self control, no amount of temptation can sway you to do evil deeds. Now not everybody does not have that kind of self control (including myself) but we can strive for it. That is the test we need to pass minimally. If you see that evil can be overwhelming than all you can do is to walk away from the situation. And the biggest battle is the temptation not to fall for the wrong stuff and even if you do try to come out of it as fast as possible. Anger is such a part of the evil empire that if you can control your anger you can save yourself from the temptation of doing evil deeds. I know that this talk is getting heavy and become philosophical and that is why it is better to end it now than to be more messed up in your head.