Eu não consegui encontrar uma cópia do roteiro de Drácula: Untold, provavelmente porque ainda é novidade. Ambas as perguntas, no entanto, foram respondidas na cena em que Vlad procura o vampiro mais velho.
The elder vampire (a noble who was cursed into the first vampire after summoning a demon) explained that there were two parts to his curse. The first was that he was transformed into the monster that Vlad sees, forced to live off human blood. The second part of the curse was that he could not leave the confines of the cave, and would be trapped there for all eternity UNLESS a righteous man volunteered to take his burden.
A segunda parte é onde Vlad entra, e também explica (um pouco) o "período de espera de 3 dias" visto pelos poderes. Como vimos,
the elder still couldn't leave the cave even after Vlad accepted the deal and willfully drank the blood. It wasn't until the moment that Vlad willfully ACCEPTED the curse itself - without any hope of a cure - that the elder could finally leave the cave.
Quanto à PORQUÊ a natureza da maldição e por que sangue humano?
The demon probably chose human blood because it's one of the few substances that most people would rather die than consume. As for the loophole, the demon most likely doubted that any righteous man would ever knowingly accept such a curse, and therefore thought that he was really trapping the noble in a cave for all time.
O filme em geral contém alguns buracos de enredo gritante, mas eu pensei que esta parte foi realmente bem feita. Charles Dance absolutamente roubou todas as cenas em que ele estava, especialmente este.