Summoned to Canterlot by Royal command to attend Princess Celestia's School for Unicorns, Starjumper Astra is determined to get through the year of study without the secret of exactly what he is being exposed.

He has good reason to keep it a secret. The product of a forbidden marriage of unicorn and thestral, Starjumper is the only living Lykan in the entire world, a pony that is unicorn by day and thestral by night. The thestrals of the Nightlands call him The Cursed One, and there is nothing in the world they want more than to see him dead. If that isn't bad enough, pony folklore has a very dim view of Lykans, labelling them as bloodthirsty, savage monsters, so Starjumper's life is ruled by the secrets that he must keep. Secrets that keep him apart from other ponies, living a life of enforced solitude, a life ruled by the clock that warns him when sunrise and sunset are coming.

All he wants is to be left alone. All he wants is to study magic in peace, get through his year in Canterlot, and then move on. But a quiet, peaceful, uneventful life isn't easy in Canterlot when he finds himself tutoring the rich daughter of the socialite Fancy Pants for living money, who just happens to be a once in a generation magical prodigy with a few secrets of her own. He also runs afoul of one of the most powerful unicorn socialites in Canterlot, that holds a burning prejudice against his half-thestral heritage.

And if all that still wasn't bad enough, he also just happens to be the subject of an ancient prophecy that says that he's one of three ponies that are destined to save Equestria.

Or destroy it.