SPOILER. . .
In 1840, Roxanne returns as a vampire and her brother, guilty and miserable, prevents her from getting to her coffin, forcing her to face the sun, which immediately obliterates her.
Also, in 1897, I recall Carl Collins learning that Barnabas is a vampire. He is determined that his cousin shall be destroyed for killing Pansy Faye, his fiancee, but after Quentin betrays him, he ends up being locked in the Collins mausoleum as Barnabas is rising. Creepy!
Also, the Angelique-Alexis switch in 1970PT was pretty damned frightening, too.
The earliest Barnabas-Maggie scenes in the cemetery were bone-chilling, especially in black and white.
Love, Robin