Twilight Sparkle and Rainbow Dash take a great risk in attempting to steal one of Celestia's most prized possessions. Two guesses as to what it is.
When they catch wind that the princess is not holding true to a deal she made, they pull a desperate heist in order to hold her to her word; but, as is the usual case, nothing goes according to plan. The only remaining question that need be answered is when they fail, just how great will their failure be?