The Thing from the Sea

In 18th Century coastal Italy, the local fishermen haul in an extraordinary catch: a gigantic serpent. The Doctor identifies it as an alien, but to the ailing locals this fabled sea creature has the capacity to heal them - if only Count Otto will share it with them. When Mrs Wibbsey comes under the influence of the Count, the Doctor finds himself snared by the wicked power of a seemingly immortal magician, the infamous Cagliostro!