Three's A Crowd

Three's A Crowd is an upcoming episode of My Little Pony Friendship is Magic. It is produced as the eleventh episode of the fourth season, and the seventy-sixth episode overall.

Summary from Hasbro press release
Pinkie Pie finds her status as “super-duper party pony” in jeopardy when the mysterious Cheese Sandwich comes to town and offers to plan an epic party for Rainbow Dash. Guest voiceover by Weird Al Yankovic.