Hysteria is a central theme in Arthur Miller's The Crucible, driving the plot and influencing the characters' actions. Set during the Salem witch trials, the play illustrates how fear and panic can spread rapidly through a community, leading to irrational behavior and unjust outcomes. The hysteria in Salem is fueled by personal vendettas, religious fervor, and the characters' desires for power and control.

In Act 1, the seeds of hysteria are sown when Reverend Parris discovers the girls dancing in the woods, leading to rumors of witchcraft. The mysterious illnesses of Betty Parris and Ruth Putnam further stoke fears, as the community searches for a scapegoat. Abigail Williams, driven by her desire for John Proctor and a need to protect herself, manipulates the situation by accusing others of witchcraft. Her confession, "I want to open myself! ... I saw Sarah Good with the Devil! I saw Goody Osburn with the Devil!" sets off a chain reaction of accusations, as the other girls follow her lead.

The hysteria escalates as the court accepts spectral evidence, where mere accusations are enough for conviction. This flawed justice system allows personal grudges to be settled under the guise of rooting out witchcraft. Characters like Abigail use the hysteria to gain power, while others, like John Proctor, become victims of the frenzy. The mass hysteria is irrational and dangerous, as depicted in the cartoon "Fire!", where hysteria threatens to extinguish the torch of liberty.

Throughout the play, biblical allusions highlight the Puritan community's reliance on scripture to justify their actions. In Act 2, characters under stress turn to the Bible for guidance, as the fabric of society unravels. The hysteria parallels the McCarthy era's "red scare," where fear and suspicion led to widespread accusations and ruined lives. In both instances, hysteria blinds people to reason, resulting in tragic consequences.