In the heart of the desert, a mighty wonder stood tall - the magnificent pyramids of ancient Egypt. Sammy, a curious young adventurer, was determined to uncover their secrets.

One day, as Sammy explored the sandy dunes, he stumbled upon a mysterious sphinx, its stone face gazing out over the land. "Greetings, little one," the sphinx spoke in a deep, rumbling voice. "I have a riddle for you. If you can solve it, you may unlock the hidden treasures of the pyramids."

Sammy's eyes widened with excitement. "I'm ready! What is the riddle?" he asked eagerly.

The sphinx leaned closer and said, "What walks on four legs in the morning, two legs in the afternoon, and three legs in the evening?" Sammy pondered the riddle, his mind racing with possibilities.