Several years had passed after Tirek's defeat and everypony is preparing for this year's Summer Sun Celebration. But Twilight is not feeling well. Several nightmares are haunting her, she has got bad headaches and a really mad mood. Although Spike and the others tell her to go and fetch help, she refuses. But when some dark incidents and curses happen, Twilight realices too late, they had walked into a trap and it has snapped behind them. For the foe is inside of her and preparing her last and final strike. To turn the celebration into a true nightmare.