Near the end of this episode, after Angel has told her they only have a minute left, when Buffy is crying, if you look and listen very closely, you can actually see/hear David Boreanaz whisper "Please, Sarah, please." Using Sarah Michelle's real name instead of Buffy.
Throughout the whole episode Buffy has a band-aid on her finger. If it was such a minor injury that it just needed a band-aid, it should have healed quickly because of her Slayer powers.
In Angel's office he is fighting the demon very close to the broken window, but visibly flinches from the rays of light in the sewer.
You can see Angel's reflection on his desk when adjusting his clock.
Angel: Look, Buffy will always be a part of me, and that's never going to change, but she's human, and I'm...not. And that's also never going to change.
Buffy: (Listening to Angel's heart beating) That's a good sound. Thump-thump, thump-thump.
Angel: It feels pretty amazing.
Buffy: I'm so glad we didn't logic ourselves out of this. We'll make it work, right?
Angel: We will.
Buffy: I'm so sleepy. But, I still want...
Angel: What? You couldn't possibly. Not that I wouldn't...
Buffy: (chuckles softly) No. No. I'm spent. Pleasantly numb even. You?
Angel: For now.
Buffy: No, I wanna stay awake. So this day can keep happening.
Angel: Sleep. We'll make another one like it tomorrow.
Buffy: Angel. This is the first time I've ever really felt this way.
Angel: What way?
Buffy: Just like I've always wanted to. Like a normal girl, falling asleep in the arms of her normal boyfriend. It's perfect.
(Buffy and Angel fall asleep in each other's arms)
Angel: It's heading toward the ocean.
Buffy: Are you sure?
Angel: It's wounded, I can smell its blood.
Buffy: Oh, right… handy skill.
Angel: The Oracles are giving us back the day, turning back time, so I can kill Mohra before his blood makes me mortal.
Angel: Another minute.
Buffy: A minute? No. No, it's not enough time!
Angel: We don't have a choice. It's done.
Buffy: How am I supposed to go on with my life knowing what we had? What we could have had?
Angel: You won't. No one will know but me.
Buffy: Everything we did.
Angel: It never happened.
Buffy: It did. It did. I know it did! I felt your heart beat.
Cordelia: I'm in some real pain here and all you can talk about is Angel. Has it even occurred to you how this whole being human thing might affect me?
Buffy: Regrettably, no.
Angel: I'm sorry I kissed you like that.
Buffy: You are?
Angel: Not for the kiss itself.
Buffy: Good. I mean, 'cause, as far as kisses go, I thought that it was well above average.
Cordelia: This plant was thriving just this morning. Now look at it. I'm telling you, where she leads, dark forces follow.
Doyle: Buffy gave it mites?
Cordelia: How else do you explain it?
Cordelia: I'm jealous of her? Please!
Doyle: Just a theory.
Angel: I love chocolate! Ugh, yech. But not, as it turns out, yogurt.
Buffy: I don't need you skulking around, trying to protect me ... unless, of course, I'm in some gigantic fight to the death, which I was last night. That was you helping me, wasn't it?
Angel: I was in the neighborhood. Skulking.
Angel: How come I get the feeling you're not telling me everything?
Doyle: Because I'm not.
Angel: (after turning human) Oh my God. Food. This is unbelievable...this is so...I forgot how good it all tastes when you're alive.
Cordelia: Yeah, they didn't even have cookie-dough-fudge-mint-chip in your day.
Angel: Oh! I want some. Can you get that?
Cordelia: It'll go straight to your thighs.
Angel: It's complicated how this all happened, Buffy, you know. It's kind of a long story.
Buffy: Your new sidekick had a vision, I was in it, you came to Sunnydale?
Angel: Okay, maybe not that long.
Angel: I didn't want to stir things up.
Cordelia: You don't want to stir, but if my ex came to town and was all stalking me in the shadows and then left and then he didn't even say hello, I'd be...
Buffy: A little upset. Wouldn't you?
Doyle: (looking towards Buffy) Don't you want to wake the girl?
Angel: Not for the world.
Cordelia: Batten down the hatches, here comes Hurricane Buffy!
Doyle: You think? Maybe he's over her.
Cordelia: You have so much to learn Little Irish Man.
Mohra Demon: The End of Days has begun and cannot be stopped. For any one of us who falls, ten shall rise.
Buffy: You hurt my boyfriend!
Mohra Demon: A great darkness is coming.
Buffy: You got that right!
Doyle: Did you hear that?
Cordy: Yeah, the Angel and Buffy Show. First they talk out their differences, then they punch them out.
Doyle: Shouldn't we...?
Cordy: Stick our noses where they don't belong and get them flattened? No thank you.
Doyle: I'll finally be free to go out and make me own mark in the world.
Cordelia: We had a cat that used to do that. Oh, God! What am I gonna do? I'm good for exactly two things: international superstardom, and helping a vampire with a soul to rid the world of evil. That makes for a short but colorful resume.
Buffy: You know, it's a good thing I didn't fantasize about you turning human about ten zillion times...because today would have been a real let-down.
Doyle: So, that's the Slayer.
Cordelia: That's our little Buffy.
Doyle: Well, she seemed a little...
Cordelia: Bulgarian in that outfit?
Doyle: Naw, I was gonna say 'hurt'.
Cordelia: Yeah, there's a lot of that when they're together. Come on.
Angel: The gateway for lost souls. It's under the post office?
Doyle: Yeah, kinda makes sense when you think about it.
Cordelia: Oh, they'll be into this for a while. We still have time for a cappuccino and probably the director's cut of Titanic.
Female Oracle: (about Angel) This one is willing to sacrifice every drop of human happiness and love he's ever known for another. He is not a lower being.
Cordelia: (about Buffy and Angel) They get groiny with one another and the world as we know it falls apart.
Cordelia: (about Buffy and Angel) Oh, please. They've got the forbidden love of all time. They've been apart for months. Now he's suddenly human? I'm sure they're down there just having tea and crackers.
Buffy: Friend of yours?
Angel: Never saw it before.
Buffy: It was rude. We should go kill it.
Angel: I'm free.
Buffy: Angel? You okay?
Angel: I feel weird.
Buffy: I know. I do, too. I mean, I only came to see you so I could tell you face to face not to see me face to face anymore. And I know there's a fly in that logic ointment somewhere, but the next thing I knew, we were being attacked by this Mutant Ninja Demon Thing, and we're on the floor on top of each other, and it's just really confusing being around you.
Angel: No, I meant I felt weird from the demon's blood. It's powerful.
Buffy: Okay. Let's just rewind Buffy's little outburst and pretend it never happened.
Cordelia: Oh my god! She killed him! (touches dust) Oops. My bad. It's just dust. I forgot to clean under the rug.
Doyle: What are you trying to give me a heart attack?
Cordelia: Hey, don't blame me if he's too cheap to hire a cleaning lady.
Oracle: I like time. There's so little and so much of it.
Buffy: So, what, you just took a whole 24 hours to weigh the ups and downs of being a regular Joe and decided it was more fun being a super hero?
Angel: You know that's not it. How can we be together if the cost is your life or the lives of others?
Buffy: I'll never forget, I'll never forget, I'll never forget. (flash) So, then let's just stick to the plan. Keep our distance until time has passed. Given enough time, we should be able to . . .
Tim Isle and Fernand Bos were nominated for the 2000 Golden Reel Award for "Best Sound Editing - Television Episodic - Music" for this episode.
Joss Whedon states in the Season 5 DVD featurette "To Live and Die in L.A.: The Best of Angel", that this episode is one of the best episodes of Season 1 and of the series as a whole.
When Angel and Buffy meet outside right after he is turned human, the scenes were filmed against the background of the Santa Monica Pier and Pacific Park.
When Buffy sees Angel and she is admonishing him for not letting her know he was down in Sunnydale, she says:
Buffy: What is it? You can see me, but I can't see you? What are we playing here?
In the Buffy the Vampire Slayer episode "Pangs," Giles says the same thing to Angel when Angel comes to Sunnydale.
Giles: It's not fair. You know that's what she'd say. You can see her and she can't see you.
This episode hints at the Season 7 finale of Buffy the Vampire Slayer, with the great war, "The End Of Days" which is also the title of Buffy episode 7x21.
In a recent issue of Angel Magazine in the U.S., there was a poll for top 25 favorite episodes, and this episode was ranked #1.
The title of the episode, "I Will Remember You," is also the name of a song by Sarah McLachlan. McLachlan's songs have been used in two episodes of Buffy the Vampire Slayer, "Becoming Part 2" (2x22) and "Grave" (6x22).
A song with the title "I'll Remember You" by Sophie Zelmani also plays at the end of the episode "Angel"(1x07) of Buffy The Vampire Slayer.
In the final seconds before the time rolls back, the Buffy/Angel theme "Close Your Eyes" (from the second season finale of Buffy the Vampire Slayer, "Becoming Part 2") can be heard. Just as in that episode, the song plays when the two realize that they can never truly be together. It is, again, composed by Christophe Beck (who scored this season of Angel, and that season of Buffy the Vampire Slayer).
When Buffy says "I was really jonesing for another heartbreaking sewer talk." to Angel in the sewers, she is talking about the time when Angel told Buffy that he no longer wanted a relationship with her and he was leaving town, again in the sewers in Buffy the Vampire Slayer season 3 episode "The Prom."
Although we hear from the Shanshu Prophecy (in which Angel becomes human after fighting the apocalypse) in episode 1x22 "To Shanshu in L.A," for the first time, in this episode we hear about the "becoming human after the apocalypse" reward. The Male Oracle reacts with a hint (about the Shanshu) on Angel's becoming human in this episode.
This is the first of two crossovers Buffy (Sarah Michelle Gellar) makes from her show onto Angel, both in this season.
Clock on Angel's wall
The clock shown during the last conversation that Buffy and Angel have before the day is swallowed is a Howard Miller clock. Howard Miller is the largest grandfather clock company in the world, but also designs other styles of clocks including desk clocks, wall clocks and more.
Rah Ice Cream
If you look closely, the ice cream container Buffy and Angel are eating out of is "RAH" ice cream. This may be an allusion to the cheer "I Scream, You Scream, We All Scream For Ice Cream" (1927 - Howard Johnson, Billy Moll, Robert Kin)...the next line of which is "Rah! Rah! Rah!"
Buffy: You're human for like a minute, and already there's cookie dough fudge mint chip in the fridge.
Although there's no such ice cream as cookie dough fudge mint chip, the mention of it lends a nod to the emergence of specialty ice cream flavors by companies like Ben and Jerry's, Dreyers, and Haagen Daas that throw pretty much everything but the kitchen sink into the ice cream. i.e. chocolate chips, caramel, brownies, cookie dough, peppermint patties, peanut butter cups, etc, all piled on top of whatever flavor the actual ice cream is. Of course this adds up to some of the most fattening substances on earth, but it's endless variety, and mighty tasty stuff.
Buffy: Tunnel number one it is.
This line refers to a TV game show called Let's Make a Deal where contestants often had to choose between door or curtain number one, two, or three. Often there would be only one good prize and two booby prizes.
Doyle: Orson, we're in a situation here.
There are at least three possible explanations for this.
1. Angel was gorging himself on food at the time so, Orson may refer to Orson Welles. Orson Welles was a famous actor/director who in his latter years was known for his girth and huge appetite.
2. Orson may refer to a character on Garfield and Friends. Orson was a pig and the one every one turned to when something went wrong. Doyle may know this because he taught grade three and might know some of the tv shows his students watched.
3. He's referring to Orson from the tv show Mork and Mindy. Orson was Mork's superior and Angel is Doyle's superior.