The royal court of Canterlot welcomes its newest member with open forelegs: the human philosopher Voltaire, from Earth.
On Earth, Voltaire is known as the greatest enemy of tyranny in the history of literature, and a legend in his own mind.
On Equestria, the court betting pool is giving him a week before the Princess banishes him to the Moon.
Note: This story doesn't have sequels per se, but there are a couple of short follow-ups set in the present day ("Parade Coverage" and "Secret Histories"), and a prequel of sorts in "At the Inn of the Prancing Pony".
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The philosopher Voltaire finds himself in the most-frustrating place imaginable: Equestria
Twilight's accidentally landed her friends on Earth, and it's up to Princess Luna to save them. But do they really need saving?
Twilight and her friends discover that the link between them extends back in time, not just to Rainbow Dash's first Sonic Rainboom, but hundreds of years earlier.
Celestia awakens from an enchantment to discover that Equestria has been taken from her.
Pinkie offers to paint a portrait of Rainbow Dash while talking about cartoons and self-confidence