S3, E4: Frustrated that Carrie has insisted on tagging along for a school assignment, Mary and Laura fail to keep a close eye on her. They live to regret this when the little girl wanders off and falls into an underground mine shaft. Despite the frantic efforts of everyone in town, the only person who can really help is the knowledgeable Mr. Laudy, an alcoholic ex-miner who now has a shot at redemption.