Twilight realizes she was a less than stellar friend to her former buddies in Canterlot, so she returns with Spike to make amends.
"Get your muzzle out of those books and make some friends!" That's what Princess Celestia tells Twilight Sparkle. She may be the smartest unicorn in Equestria, but Twilight Sparkle gets an "incomplete" in friendship. There's more to life than learning magic, after all - so she goes to Ponyville on a mission to make friends. There she meets five special ponies who take her on exciting adventures and teach her the most powerful magic of all... the magic of friendship!