How is tension created in The Monkey's Paw?

Answer 1

When the son is brought back from the dead, the parents begin to think about what he will look like. But, remembering the nature of his accident, we are left to imagine the grotesque mangled mess he must be in. As he's walking up the walkway, the sounds he makes and the way the writer couples the growing trepidation of his parents with each step he takes builds up a lot of tension. The tension reaches its peak when they finally hear the knocking on the door, and are too afraid to answer it due to the abomination they had slowly created in their heads of their son's image.

However, it's not just about what he looks like makes his parents afraid. They also begin to think of the evil behind what was done, and this contributes to the growing tension. The fact that our minds are never relieved with a description about what the son actually looks like in reality is the tease that keeps us on edge.