Critics also note the entertaining methods used to drive the plot. When Atticus is out of town, Jem locks a Sunday school classmate in the church basement with the furnace during a game of Shadrach. This prompts their black housekeeper Calpurnia to escort Scout and Jem to her church, which allows the children a glimpse into her personal life, as well as Tom Robinson's. Scout falls asleep during the Halloween pageant and makes a tardy entrance onstage, causing the audience to laugh uproariously. She is so distracted and embarrassed that she prefers to go home in her ham costume, which saves her life.