Does the monster ever return?

Do you mean at the end of the story? I don't think we are ever told. The next day, the two men are rescued and claim that the waves were responsible for the damage. A year later, a new lighthouse was built, but the narrator already had a new job on land. One night, he drove down and parked near the lighthouse to listen. The monster never came back, according to McDunn. As the narrator listened to the Fog Horn, he believed it sounded like the monster, and he wished there was something he could say in return.