Movies have the capability to evoke a range of emotions. Laughter, sadness, excitement and resentment are a fraction of the effects films can have on us, as cinematography, acting, set design and sound engineering combine to create epic moments; moments that become etched in our minds for quite some time later.
Revenge is a plot device so often used in thriller, action and suspense flicks, and its fruitful use by filmmakers is no surprise, as the pursuit of vengeance is often such an enthralling path. Spawning an entire genre of film, revenge's capability to create a compelling narrative is obvious. Being the retaliation for a past wrongdoing, the expectation is that the payback for said action is far more brutal than the original crime.
Though it's often incredibly satisfying, acts of revenge have been known to push the boundaries of brutality from time to time. Vengeance so frequently manifests itself in the form of violence, and the violence that ensues often isn't for the squeamish, no matter their potential justification.
From betrayed protagonists to despicable, deranged nutcases inflicting immense pain on their victims, these vicious acts of revenge were as brutal as they come.