Welcome Back to the Hellmouth
A slightly bananas idea I had to rewatch (for the third or fourth or fifth or seventeenth time, episode depending) Buffy the Vampire Slayer — exactly 20 years after each episode’s original airdate.
Welcome Back to the Hellmouth: "Halloween"
In the Buffyverse, Halloween is amateur night. Fake ghouls and goblins only; the real ones take the night off. Except when they don’t. The episode’s cold open is all Buffy, fighting a random vamp (her stunt double’s hair has improved notably!) while another vamp lurks in the shadows, filming so Spike can study up on his new Slayer opponent. Smart man.