Equestria Girls is a My Little Pony: Friendship is Magic spin off movie, set in an alternate world where humans live instead of ponies. Twilight, as her first job as princess, must travel through the portal and into the alternate world to take back her crown, which was stolen by Celestia's former studen Sunset Shimmer.
She arrives at Canterlot High with Spike, to find she's transformed, and so has Spike (Now a dog). Together, they try their hardest to get the crown back, by winning the title of the fall formal princess, that has been taken by Sunset Shimmer year after year.
As she tries her hardest to win the crown, she befriends 5 girls, all exact replicas as her friends back in Equestria. Together, they win the crown and Twilight is able to return to Equestria through the portal.
Written by Meghan McCarthy