5.6 - The Vampires of Venice

From wikipedia

The Doctor, believing Amy's attraction to him is due to the stress from travel, gatecrashes her fianc? Rory's stag party, and invites the two of them on a romantic trip courtesy of the TARDIS. They land in Venice in 1580 and soon find trouble. The city's patron, Signora Rosanna Calvierri, claims that the Black Plague runs rampant outside of Venice, but the Doctor says this is false and it appears she is using this as an excuse to seal off the city. When they try to learn more, they encounter Guido, a boat-builder who is desperately seeking information on his daughter Isabella. Guido explains that Signora Calvierri runs a highly-praised school for the betterment of young ladies, which he was able to enroll Isabella into, but he now fears something is wrong. The Doctor and Amy and Rory investigate separately; they all come to the same conclusion: Signora Calvierri, her son Francesco, and the girls in the school are all vampires, feeding on the blood of young women by biting their necks with long teeth. These vampires fear direct sunlight, and leave no reflection in a mirror.

24 out of 99 (24.2%) raters say this story requires a previous story.