This is one of televisions finest moments. From Sarah Michelle Gellar and David Boreanaz's acting to the wonderful story this episode will sure have you intrigued from the first second to the last. This is a major episode to the story arc of season two and I highly recommend you either know the story of season two before watching or don't skip it if your watching on DVD (if you do you'll be sorry).
This episode's main focus is Angel. Seeing his life from the start up until now makes you feel sorry for what Angel has become and makes you cheer for his hearty return. Drusilla, Spike, and Angelus hatch up a plan to awaken the demon Acathla and send the world spirally into hell (literally). As this is going on Willow, Buffy, Xander, Giles, and Cordelia find Ms Calender's disk (which everyone was probably rooting to happen) and they start their death defying spell of returning Angel's soul into Angelus.
The first thing that hit me from the opening of this episode was the speech given from Angel's watcher much like in the episode "Passion" where Angel gives his little speech throughout the episode. From that moment, I knew this would be a great one. I held on, strapped in, and was taken for a ride as the story of Buffy and Angel slowly comes to climax. The acting by Sarah and David is up there with their top performances on the show and is a sure fire Globe deserver. I loved seeing Angel's past starting from the very beginning up to this point and time. It really makes you feel sorry for Angel that all he wanted was to help Buffy since the first time he saw her back in Los Angeles. I also loved seeing Buffy from beginning (although it isn't much different from the movie, but still...it was with Sarah). Seeing Willow get deeper into her witch side is awesome again (just wish I saw some Oz). The episode before this, "Go Fish", also helps to make this episode seem much more structured and exciting (as it goes from a monster-of-the-week to a story arc episode.) The ending is great and I won't ruin it for people that haven't seen but overall its worth the watch.