However, when they discover that their potion is actually a poison that causes Cheerilee and Big Mac to become overly obsessed with each other, they must find a way to reverse its effects.

The Cutie Mark Crusaders - Apple Bloom, Scootaloo, and Sweetie Belle - discover that their teacher Cheerilee lacks a "very special somepony" to be with on Hearts and Hooves Day.

The three happen across Twilight Sparkle, reading a book about Hearts and Hooves Day, including the recipe for a potion purportedly able to make a couple fall in love.

Though initially pleased, the Crusaders realize this is not the desired result, and upon consulting the book, learn that the potion is actually a poison that caused Equestria to fall into chaos centuries ago when the prince and princess who drank it were too lovestruck to rule their kingdom.

Sweetie Belle is able to barricade Cheerilee within the Carousel Boutique, but Apple Bloom and Scootaloo lose track of Big McIntosh at the jewelry store.

Sweetie Belle and Scootaloo are able to dig a giant pit in Big McIntosh's path, but when he falls in, his cries alert Cheerilee to his presence, and she bursts out of the Boutique.

[2] Leading up to the episode's premiere, the network hosted a My Little Pony Fan Favorites Mare-A-Thon that made large gains in the audience.