Friday the 13th: The Series (1987)

S3E8 Night Prey

Two decades prior, a man loses his fiancée to vampires, who turn her into one of their own. Driven by obsession, he dedicates his life to hunting these creatures until he discovers a cursed antique cross that grants him the power to not only repel but also incinerate vampires. However, to activate the cross, he must sacrifice someone. Tragically, his friend, a priest, becomes the first victim. As events unfold, it is revealed that his fiancée has embraced her vampire existence willingly. In the end, the story concludes with the deaths of both the vampire hunter and his lost love.