Carpe Noctem - S3-E4
Trivia: The episode title is a play-on-words of the Latin phrase "Carpe diem," which means "Seize the day." "Carpe Noctem" literally means "Seize the night."
Trivia: Fred's Mum says that her Dad enjoys films like Alien, except for the last one, during which he fell asleep. Joss Whedon wrote the original screenplay for Alien Resurrection but it didn't turn out in any way, shape, or form how he envisioned:he now claims he wants to tour the country lecturing on how not to make films using only this film as an example.
Trivia: By season's end, Darla has died four times: (1) in flashbacks to when she was sired by The Master, (2) when Angel dusted her in the Buffy episode "Angel", (3) when she was re-sired by Drusilla, and (4) when she dusted herself so that Connor could be born.
Heartthrob - S3-E1
Trivia: When James and Elisabeth are expressing their love for each other, Angelus comments "give it a century". This is the same thing The Master said about Angelus and Darla's relationship.
Trivia: The prima ballerina is played by Summer Glau, who also appeared on "Firefly". In addition to acting, Glau is a classically trained ballerina.
Answer: Everybody including Angel saw her. After helping them and then being left alone to talk to Angel, Cordelia says that the Powers That Be let her come back one more time to help them. After Angel gets a call saying that she died, he realises that it was her spirit that was helping them the entire time.