18+ Coltmas is tired. For ten years has he served in Her Highness' Secret Service. For ten years has he abandoned his own hopes and desires, exchanging them for the interests of Equestria. Now that he is finally able to retire, what could prevent him from doing so? Only a puzzle - a mystery that needs to be solved. Will he be able to combine his oath and the grim reality? Will he be able to remain loyal to the end? And if yes, then to whom?

*Crossovers with all spy stories, I guess*