This story is a sequel to Doctor Whooves 3: The End of the Universe

While it's only been five months for Twilight, but for The Doctor, it's been two years. Now he's returned to Equestria and is back as the 10th Doctor, and Twilight is very glad to see him. Looking for a break from her royal duties, The Doctor takes Twilight to where he comes from, which just happens to land at Canterlot High. But, the vacation is cancelled when a student is dead with a strange virus of Zygon origin. With the help of Sunset Shimmer, The Doctor and Twilight must save all mankind from the fatal Zygon disease.