The day of the next Solar Eclipse is fast approaching. It occurs when the moon passes over the sun, sending the world into total darkness for a short time. Princess Celestia is worried about what will happen on this fateful day, because before Nightmare Moon was defeated, she put a curse on the sun and moon, so that the princess's magic could not interfere with the eclipse. Why did Nightmare Moon set this dreadful curse? It has no purpose… at least, that's what it seems. Celestia fears for the safety of her sister Luna.