IT, most commonly known in its favored form as Pennywise the Dancing Clown, is the titular main antagonist of Stephen King’s novel It.

A supernatural, shape-shifting alien entity, It arrived on Earth sometime in the 16th century. Upon discovering that its natural food source did not exist on this planet, it adapted by preying on human children. Feeding every 27 years, It takes on the form of its victims’ worst fears—believing that terror “salts the meat” and enhances the flavor. While Its true form cannot be comprehended by the human mind, Pennywise the Clown became Its primary guise, adopted after witnessing a performer in the 1800s dressed in clown attire. Clowns, being a common fear among children, suited Its predatory needs.

Roughly 300 years after Its arrival, It claimed the life of Georgie Denbrough by dragging him into a storm drain. This act set off a chain of events that led Georgie’s older brother, Bill Denbrough, to form the Losers Club—a group of outcast children determined to confront the evil haunting their town of Derry.

The Losers battled Pennywise and inflicted such a severe defeat that It retreated into hibernation. Believing that the now-adult Losers would no longer pose a threat, It reawakened 27 years later to resume feeding. However, the group returned to Derry, determined to end Its reign of terror once and for all.

Despite initial struggles to stop the killings, the Losers eventually confronted It in a final battle. This time, It appeared in a form closest to Its true essence—a colossal, nightmarish spider-like creature. In this form, It managed to kill Eddie Kaspbrak before the Losers overpowered It. They broke Its legs, crushed Its head, and ultimately destroyed the creature by ripping out and crushing Its heart. With Its physical form destroyed, the entity’s essence—known as the Deadlights—faded, marking the end of Its terror.