A full night of uninterrupted sleep is often taken for granted, yet it’s crucial for waking up refreshed and fully productive the next day.

Many assume that simply going to bed at a reasonable hour guarantees rest, only to find themselves awake in the middle of the night—most commonly between 3:00am and 5:00am. Struggling to fall back asleep can leave one groggy and exhausted, impacting daily performance.

Interestingly, this phenomenon isn’t just a random quirk of sleep patterns or bad luck. There’s a deeper significance to why so many people wake up during these particular hours.

The period between 3:00am and 5:00am has long been referred to as the “hour of the wolf,” a phrase popularized by Swedish director Ingmar Bergman in his psychological horror film of the same name. Bergman described it as “the hour between night and dawn… when most people die, sleep is deepest, nightmares are most real. It is the hour when the sleepless are haunted by their worst anguish, when ghosts and demons are most powerful. The hour of the wolf is also the hour when most babies are born.”