When Harvey Guillén first learned that his “ What We Do in the Shadows ” character, Guillermo, would finally be turning into a vampire, he thought the show was ending. “They didn’t tell us that Guillermo was going to become a vampire until we had our meeting for the beginning of the year,” the actor recalls on a video call from Spain. “I thought we were going to wrap it, because where else do you go with his character?” But it turns out the writers of the acclaimed vampire mockumentary did have more stories to tell.

Among the storylines audiences will see in the sixth and final season of “What We Do in the Shadows,“ which launched last week and airs weekly on Mondays through Dec. 16, is Guillermo’s efforts to figure out what to do with his life now that he needs to move on from his lifelong dream of becoming a vampire. In the finale of Season 5, Nandor gives Guillermo a choice — become a vampire or return to being a human.

He chooses to remain human, but it meant sacrificing Derek (Chris Sandiford), his friend and the vampire who turned him. (Derek is saved, though — he’s reanimated by the Necromancer (Benedict Wong) in exchange for the cash Guillermo paid Derek to turn him — minus $270 he spent on “vampire clothing” from Hot Topic.) “A lot of what this season is about is his efforts to break away and start his own separate normal life and the vampires then following him to quote-unquote help him on his way in the real world,” says “Sha.