Mad Science
The entire premise of Frankentein is constructed upon a sense of irony. Without Henry Frankenstein's conviction that his experiments are going to benefit humanity, deaths could not occur and the town's food supply would not be placed in peril as a result of the mill burning to the ground.
Light and Heat
A subtle example of irony that is used for the purpose of setting in motion a major plot point is the sequence where the Creature get his first exposure to the concept of warmth as both life-affirming and an object of terror. In just a matter of minutes the viewer is taken on an emotional joyride in which the Creature reveals just childlike and abandoned he really is by holding up his hands to the warmth of a suddenly bathing his miserably dank prison. In this moment, the Creature becomes a pathetic object of pity capable of reminding us that his body still carries the coldness of death. That aching reach for the warmth provided by sun is swiftly slashed through with irony in the image of Frankenstein’s sadistic and incompetent assistant Fritz rushing in with a lit torch which instantly transforms the concept of warmth and heat from a thing to reach out toward into a weapon to cower from in fear.
Innocent Blood
The villagers ultimately set a course of moral self-destruction for themselves by jumping to conclusions, which in turn lead to taking the law into their own hands. The Creature end the film running for his life to escape the pursuit of villagers who in their rush to judgment have actually become the embodiment of evil whose misunderstanding result in the premature death of an innocent. Kind of like when the Creature’s misunderstanding accidentally result in the death of the innocent little girl.
Food for Thought
The misattribution of the death of the little girl to the Creature as a result of purely evil malevolence engenders fear among them so great that they only way they can see to ensure the monster does not destroy everything and everyone is kill it. Chasing Frankenstein and the Creature to the mill results in the structure being burned to the ground. The likely outcome of this unforeseen, but avoidable outcome is pure irony. In the first place, the Creature could probably have become an ally capable of providing security from outsiders since he was not an evil killer in the first place. Secondly, because they did rush to judgment and did allow the mill to burn, the food supply is likely to cause far more devastation than the Creature ever could have.
Now He Knows What Parents Feel Like
Up in the mill, Frankenstein finally—finally—learns what it is like to be god. It is not enough merely to give life—woman have been doing that millennia. What Henry learns up there in the mill beneath the turning of the wheel is that he may have given life to the Creature, but Creature is no longer a baby dependent upon his parent to meet every need. The Creature outwits the doctor and for just a moment there is an ironic twinkle of appreciation at his own skill, even as that kill seems to imply certain and imminent death.
