Welcome to the Hellmouth
Here is my little detail-induced description:
Theme of ep: Irony
First scene:
Notice the music. It is very typical of Dracula style old movies. Gothic sounding. I checked the credits and the composer is Walter Murphy.
Also, note that the scene is a stereotypical setup of an innocent girl getting killed.
Darla's outfit is that of a school girl's uniform. Plaid miniskirt, stockings (I think), cardigan, collared blouse. Her hair is blonde. All of her look points to her being the victim.
The guy is wearing a leather jacket which seems more threatening than Darla's apparall.
As we see, the situation switches to the biy being the victim, when we find out Darla is a vampire.
When the credits roll, notice the font in which "Buffy" is written. It is in the style of papyrus or something like papyrus...maybe Little Richard. In season two and on, "Buffy" is written in Gothic style font.
When we first see Buffy, she is in bed and having nightmares. Some of these dreams depict later episodes. Also, Giles later asks her if she has been having nightmares - this being an indication of her as a Slayer and the fact that they are positioned on a Hellmouth.
The prinicpal at Sunnydale High (for the first few episodes) is Principal Flutie, the same one from the Buffy movie.
During Flutie's and Buffy's discussion of her previous school, Buffy mentions:
"You're not seeing the big picture here. That gym was full of vamp- asbestos."
This may be an allusion to the movie, as the last scene of it was the gym being overrun by vampires, but also a good message. This is the first time we here the mention of "The big picture" which I think is a big theme throughout the show's running.
As the day starts out, notice Buffy's outfit compared to everyone else's. It's trendy, valley, and preppy. Most other people's clothes aren't as nice. This may be because of Buffy desperatley wanting to fit in and find friends.
In Buffy's first class, the first thing we see is a chalkboard with the word "Death" written on it. The teacher talks about the Black Death that killed many. But, oh, the irony.
Also, on the backboard are written:
"What, if anything, was gained scientifically?" and
"What were the repercussions?"
I know it's just a coincdence, but those seem to be big themes in season four.
Cordy is introduced and one of her first lines is "I'd kill to live in LA". An ironic statement being that she does ending up living in LA and killing things there.
When Buffy heads into the library, she is greeted by Giles with a book entitled "Vampyr". This is the first and possible last time we see this spelling of the word. I believe it is the older of the two spellings.
When Ora finds the dead body in her locker, why couldn't she smell him? Don't even bitten and sucked dry bodies leave an odor?
After Cor's mean comment to Willow, Buffy tracks her down. This isn't only another display of Buffy trying to make friends, but also that Buffy is a very nice person.
Xander and Jesse shortly follow after Buffy's arrival. Xander's comment "Well not much goes on in Sunnydale" is yet another example of irony and how very much goes on in the town.
This is just my opinion, but in the way Giles describes Sunnydale and how it attracts "mystical whozits", seems to be very similar to the occurances on ley lines.
Buffy makes her first speech on how hard being a Slayer is. not the physical training/endurance aspect, but the fact that she can never have any contacts or relationships to that of her Watcher. That she can't have friend's or family who know of her identity, because she might endanger them. She states that nothing, not even her Watcher, could prepare her for that.
Luke, the lead vampire, the strongest on so far, makes a prayer (A vamp prayin? Irony) during his revival of the Master:
"The world will bleed." Note the line in Restless (and possible other episodes) "The bloody cry. The penetrating wound." Similar in that both depict visions of blood and pain, yet one describes vamps and the other - a Slayer.
When Angel and Buffy first meet, he throws off any sign of him being evil. Or even a vampire. "I don't bite" and giving her a cross.
Angel: "You're pretty spry though." This line came shortly after Buffy was doing a handstand on a bar. In OMWF, season six, Buffy says "I'm pretty spry for a corpse" after doing a handstand on a vault.
Take in consideration that Angel seems to know about the Hellmouth, it's title and form, ("You're standing at the mouth of Hell") and yet Giles doesn't yet have a name for what it is.
At the Bronze, Buffy seems flirtatious and witty, always chock full of puns. This would tie in with Buffy's strength. (In Helpless, Buffy makes the comment during her lack of skills "If I was still the Slayer, I'd be punning it right about now") Yet Willow has no puns, no jokes, only vowel sounds. Her strength in correlation, seems to be lacking.
Buffy says to Willow: "Sieze the moment. Cause tomorrow you might be dead." Note to Jesse.
Buffy and Giles meet up. Giles desperately tries to make Buffy "see" vamps with Slayer skills - the "right" way. Buffy uses her own logic; this later results in B accidentally attacking Cordy.
Sidenote: Xander had earlier called Buff's wooden utensil a "stake" yet Cor called it a "stick".
In the masoleum, we see the first dusting of a vampire. Also, in this scene, Luke makes the comment "You have no idea what you're dealing with" which in later seasons becomes a line for Buffy to use.
Luke recites a prohecy that Hell will reign on Earth. This is what we will eventually see when the Hellmouth opens.
Ok, this might not be a one and only thing, but I just noticed here that the Grr Argh monster had a shadow!!!! Hehee.