Flamesoar and Firebird are two twin sisters who live happily in Canterlot. But during one little jumping competition everything goes down hill.

Rainbow Dash finds out that Mare Do Well has returned and that none of her friends are responsible. So who could it be?
Mare Do Well copes with the secret of being mysterious.
Based off of the comic on deviant art entitled Dark Mare Returns found here http://tan575.deviantart.com/art/The-Dark-Mare-Returns-commissioned-316687526

Flamesoar is a unicorn mare with three legs who is working in a program run by the wonderbolts.
She is joined by her depressed sister and a wonderbolt with an anger management disability. Feather an alicorn, wonderbolt is set as their supervisor and together they try to fix their problems.