"I'm not saying that we should kill a teacher every day just so I can lose weight!"
In many ways, this is more-or-less a typical Buffy episode. You have your toolish, jealous Xander and his unrequited love for our heroine, yet another murder at Sunnydale High, and...a gigantic praying mantis disguised as a substitute teacher who looks like Julie Cooper and seduces students so she can use their sperm to fertilize her eggs. Oh, and then she decapitates them.
The plot is loosely as follows: Xander's got it bad for Buffy, who doesn't want to be with him (because he's TERRIBLE). He fantasizes about rescuing her, which he cannot (because he's useless). He hates Angel with his "girlie name" and his leather jackets, and decides to go for the new substitute teacher, who--surprise!--is actually a praying mantis who eats grasshoppers on toast for lunch.
(About that teacher/mantis. Her name is Ms. French, and her accent is South African. She looks EXACTLY like Julie Cooper, the world's greatest character ever to grace television, but she ISN'T! )
After giving Buffy some sass about how she's just jealous that he found someone, he goes over to Ms. French's house to help her work on a "class project" wink nudge! She gives him a martini and asks if he's ever been with a woman. This seems like appropriate student-teacher behavior! But as she starts feeling him up, he watches in drugged confusion the teacher-to-mantis transformation, astutely remarking, "Your hand is so...serrated!" Before he knows it, he and another kid are locked in cells in the basement and are in need of some rescuing. The Scoobies are happy to oblige, but at great cost to Xander's precious ego, as it's revealed that he was chosen because he'd never had sex with a woman LOL!!!! You at home will be thinking, why, I find it hard to believe that girls around the world don't line up for this man of men!
Somewhere around this episode I decided to turn my brain off re: Angel for the rest of the series and enjoy the ride--quite early on, as you'll see--because seriously, what is he mumbling about? Ever? At some point, Buffy comes across Angel in a park, and upon my first viewing, my two friends and I had to sit down, slow-mo, and take notes to figure out wtf he was talking about. It turns out he was warning Buffy about the death of a homeless man; I heard homeless man, which I decided couldn't be correct because why would Angel be talking about a homeless man, and my friends both heard "boneless man," so we were like, "Do praying mantises have bones?"
Favorite moment: Buffy suggests that Giles find a recording of bats, as praying mantises can't stand bats. At the climactic moment in Ms. French's Love Dungeon, Giles whips out his dictaphone, presses play, and! it's just a recording of his voice talking about praying mantises.