If we're looking beyond Buffy and Angel, I think the ninth episode of S2 on Game of Thrones, "Blackwater" is perfect. Everything about that episode is not just incredible, it's stunning. It culminates the build of the entire season perfectly, it has jaw-dropping action, character moments that set the standard for any show out there, it's just a perfect episode.
Absolutely- I am reasonably sure that when Bronn was singing "Rains of Castamere", I may actually have started jumping around the room in excitement. It was a brilliant episode.
From Buffy/ Angel (within the context of the show, at least):
- "Passion"- no surprises here, I guess, but it's just brilliantly put together. The episode builds up well, we know that SOMETHING is going to happen, because other than Angelus tormenting Buffy and co. there is no monster/ situation of the week to battle through in the meantime as there has been for the past 2 episodes. There's sweet moments (Giles and Jenny making up, and Buffy making peace with Jenny for their sake, Buffy and her mother having "The talk"), there's the humour of Cordelia being worried about her car. The whole episode, and in particular the scene where Angelus is spying on Buffy and Willow as they receive the bad news emphasises just how much Angelus is about the art/ cruelty of the kill. Once Jenny is murdered, we are just waiting for the point at which the rest of the gang finds out, and the scene where Giles finds her, and pretty much every scene thereafter is done fantastically. The use of the music as Giles climbs the stairs. The muffled conversations watched through the window as we see the mood in Buffy's house go from jovial to shock and misery. The scene with the Scoobies at Giles's house, particularly Buffy and Xander is well done- it highlights (as does the final scene of the episode) that Buffy realises that Angel needs to die, I think. Giles beating up Angel (and the first seeds of the notion that Spike doesn't just dislike Angelus, but will happily see him die) and the scene where he and Buffy just collapse. Plus, Anthony Head's voice appearing in the music that recurs throughout the episode ("Remembering Jenny", I think it's called) was a nice touch.
I think "Surprise"/ "Innocence" and "Becoming Pts 1/2" are also up there for consideration (the Angelus arc has some of the strongest episodes, IMO, of the show's history).
- "Hush" is another strong contender. It's one of the scariest episodes, and again, has some great moments of humour. Great concept, too, the idea of being unable to scream. Some slightly cliched moments (creepy child singing creepy nursery rhyme at the beginning).
From Angel:
- "Not Fade Away" - I think I might be a bit biased because of this being the final episode, and because I enjoyed it a lot, but I really did feel like it was well done. All of the characters got some great moments, and whilst my boyfriend described the ending as unsatisfying, I thought it tied in well to the overall theme of the show. Unlike Buffy (which is, generally speaking, about how Buffy and co. face down the apocalypse/ Monster of the week and save the day, in the end), a lot of Angel has, IMO, been about fighting the good fight because it's the right thing to do, even if you don't always win. Wolfram and Hart, for example, have been around and evil since the very start of the series, and the only thing that has come close to getting rid of it (or, the LA branch anyway) is another Big Bad. Angel Investigations never managed to get rid of it, but they fought them anyway. Had the episode gone on to show the fight scene (leaving the comics aside), they would probably all have been wiped out, but as it is, we get to see the last four standing jump into battle, because that's what they do. It's not the cheeriest thing ever, and in truth, it's not a great plan. But it is a great episode, IMO.
There's a few others I can think of from Angel, actually, but I'm going to leave it for now before I write an essay XD