In the exposition we are introduced to Mrs. Stevenson a querulous self centered neurotic. She has been trying to call her husband for a very long time but the line is busy. We also know that her husband will be working late that night.
In the rising action/conflict we know that Mrs. Stevenson finally gets connected to her husbands work line. She hears a man say hello so she says hello back, but the other person can't hear her. She decides to listen to the conversation and it turns out that 2 men are planning to murder a woman.
The rising action is continued when Mrs. Stevenson calls Officer Duffy because she is nervous that she might be the victim. The officer can't help her. She tries to call her husbands office again but the line is busy. She then decides to call the hospital so she can have one of the nurses to stay with her.
The climax occurs when Mrs. Stevenson is on the phone with a nurse and she hears someone in her kitchen downstairs pick up the phone receiver. She quickly puts the phone down and sits in terror. She hears the person up the stairs. A train goes by and Mrs. Stevenson screams.
The falling action of the story is when the murderer came and killed Mrs. Stevenson.
The resolution is when George says Sorry, Wrong Number.