At first glance, everything in this hospital room seems perfectly normal. A mother is resting comfortably in bed while holding her newborn baby, and a doctor stands nearby. There are flowers beside the bed, daylight coming through the window, and a large clock hanging prominently on the wall.

The challenge is designed to make you inspect every small detail. Many people immediately concentrate on the mother and baby, wondering whether something about the way the newborn is being held is incorrect. Others examine the doctor, the hospital bed, the flowers, or even the window searching for something that doesn’t belong.

But the real clue is hanging right above them. Take a closer look at the clock. The numbers appear to be arranged normally, and the hands initially seem convincing enough that they are easy to overlook.

The mistake is with the clock hands. On a normal analog clock, the hour hand should be noticeably shorter than the minute hand. In this picture, however, the hands have been drawn incorrectly, with the hand pointing toward 10 appearing longer while the one pointing toward 2 is shorter, creating an impossible conventional clock arrangement for the apparent time.

That tiny detail is what makes the puzzle tricky. Everything else in the hospital scene is there to distract your attention, while the answer has been displayed prominently on the wall the entire time. If the clock was the first thing you checked, you caught the hidden mistake.