There's this episode of "Buffy the Vampire Slayer" called "The Body." It's one of those episodes that always gets mentioned when talking about the show because it's so well done, and so impactful. It, and many of the other commonly-mentioned-by-name episodes ("Hush"; "Once More With Feeling"; "Tabula Rasa"), stands out in part for all the ways it breaks from the regular format of the show.
In every generation a Slayer is chosen, a girl called to defend humanity against vampires and demons, gifted with incredible strength and agility. "Buffy" is a show about the supernatural. The fantasy elements are usually allegorical, standing in for some challenge of young adulthood, but it's still a show where people come back from the dead and soulless ex-boyfriends get sent to hell dimensions. It runs on the mythological. But in "The Body" Buffy and her friends have to contend with something they're not equipped for — mortality. Buffy's mother, Joyce, dies. Not from a vampire bite or a ritual sacrifice, but a brain aneurysm. Unpredictable, unstoppable, mundane.
All the show's characters struggle with the loss, but it's Buffy that really gets thrown into the unknown. Part of the conceit, and the appeal, of "Buffy the Vampire Slayer" is that being the slayer takes its titular character from what's usually depicted as the ultimate position of weakness (an attractive young woman - always the first to die in the horror movie) and puts her a position of power. She's nearly invulnerable and always an agent of action. But her mother's death renders Buffy intensely vulnerable to forces outside her control.
From the second she discovers her mother's body, Buffy is off balance. “Mom, mom, MOM,” she shouts— like she'll be able to wake her from her motionless, blue-lipped state. Buffy spends the episode largely directionless, her eyes wide and searching. Death has a particular finality, a kind of discontinuity, that action heroes rarely have to deal with. For action heroes, there's always someone to avenge, some big bad to chase, some shadowy organization to topple. A mission, a revenge quest, , are what masculine (and ) paragons run on. But Buffy's robbed of that drive. She can't conquer natural death, not really. She doesn't know what to do without a mission.