Intrigue

Twilight Sparkle and friends follow a map to a pseudo-Utopian village where the inhabitants have given up their cutie marks. At first glance, the ponies of this village seem happy, but when the Mane Six investigate further, they realize that the village leader Starlight Glimmer has a sinister view of friendship and individuality.

Twilight Sparkle is invited to give a speech in Canterlot, of which she discusses the connections between cutie marks, and how a Sonic Rainboom made by a younger Rainbow Dash, somehow connected all of her friends together.

As she continues to give her speech, Twilight swears she sees Starlight Glimmer in the audience, a unicorn whom she helped overthrow from a small village that aggressively promoted a life-through-equality agenda.

Spike thinks Twilight may be overreacting, but upon returning to the castle in Ponyville, both are shocked when they find Starlight waiting for them. As they watch, she uses a scroll to open a ticking portal. Twilight and Spike follow her through, and find themselves back in time, on the day when Rainbow Dash made her Sonic Rainboom.

As Twilight and Spike sit back to watch the events unfold, Starlight casts a spell that incapacitates Rainbow Dash, allowing some bullying young colts to win instead.

In the aftermath, Twilight is sucked back into the portal to the present day...where she finds that Ponyville has become rundown. Of their friends, the only one who still exists there is Applejack, whose family have taken to providing food for the war efforts against King Sombra, upon whom much of Equestria (led by Princess Celestia) continue to wage war against.

Twilight and Spike return to the past again, but this time, find Starlight persuading the bullies (who had originally made fun of Fluttershy), to consider her feelings, thus throwing a wrench in Rainbow's original reasons to race.

Twilight then attempts to get the young Rainbow Dash to still pull off a Sonic Rainboom, but her insistence and telling that she's seen her "do it in the future," scares off the little filly.

The results suck Twilight and Spike back to the present, where they are soon surrounded by a group of ponies, who think them to be spies!