Horatio Hornblower, Captain of the HMS Lydia, is forced to pull into the safety of a mysterious island after taking heavy damage from a French ship. The island in question? A little land called Equestria.

Initially suspicious of the ponies, Hornblower finally consents to work with them to get his ship in fighting condition once again. As a sort of trust-building exercise, Princess Celestia has sent over some help; the bearers of the Elements of Harmony. They see it as an adventure; Hornblower sees it as a test of his sanity.