Pennywise “sleeps” because the creature It follows a natural cycle of feeding and hibernation, not because it needs ordinary rest like a human. In Stephen King’s lore, It feeds intensely for about a year on fear (mainly children’s fear), then goes into a deep 27‑year dormancy underground to conserve energy and regenerate its power.
Feeding and fear
It is an ancient, otherworldly predator that primarily seeks emotional energy, especially fear, which makes its victims “taste” better in a metaphysical sense. After a concentrated period of hunting in Derry, It becomes “sated,” like a predator after a huge kill, and no longer needs to stay active.
Hibernation cycle
Once the feeding phase ends, Pennywise retreats to its lair beneath Derry and enters a state of dormancy or hibernation that lasts roughly 27 years. During this time It does not age or significantly expend energy, allowing it to recover from the strain of its psychic and physical manifestations and prepare for the next cycle of terror.
Why it matters in the story
This sleep cycle explains why terrible events in Derry occur in clustered bursts separated by decades, and why adults tend to forget the horrors between cycles. It also gives the Losers’ Club a narrow window in which the creature is weakened or dormant, which is crucial to their ability to confront it.
