It was just after midnight.

All was quiet in the dead of night.

Dark clouds had covered the slender crescent moon. The shadowy night added some serenity and mystery to the prairie.

"Clip-clop... Clip-clop..."

The hurried clip-clop of horses suddenly sounded, breaking the silence of the night. The abrupt sound shocked all people in the camp.

Many people woke up with a start and felt inexplicably nervous. They waited for ...