After visiting 2015, Marty McFly must repeat his visit to 1955 to prevent disastrous changes to 1985... without interfering with his first trip.

Doc: The time-traveling is just too dangerous. Better that I devote myself to study the other great mystery of the universe: women!
Marty McFly: Where are we? When are we?
Doc: We're descending toward Hill Valley, California, at 4:29 pm, on Wednesday, October 21st, 2015.
Marty McFly: 2015? You mean we're in the future?
Jennifer: Future? Marty, what do you mean? How can we be in the future?
Marty McFly: Uh, Jennifer, um, I don't know how to tell you this, but I... you're in a time machine.
Jennifer: And this is the year '2015'?
Doc: October 21st, 2015.
Doc: Roads? Where we're going, we don't need roads.
Young Biff: Why don't you make like a tree and get out of here?
Old Biff: It's *leave*, you idiot! "Make like a tree, and leave." You sound like a damn fool when you say it wrong.
Young Biff: All right then, LEAVE! And take your book with you!
Marty McFly: That's right, Doc. November 12, 1955.
Doc: Unbelievable, that old Biff could have chosen that particular date. It could mean that that point in time inherently contains some sort of cosmic significance. Almost as if it were the temporal junction point for the entire space-time continuum. On the other hand, it could just be an amazing coincidence.
[last lines]
Young Doc: No! It can't be; I just sent you back to the future!
Marty McFly: No, I know; you *did* send me back to the future. But I'm back - I'm back *from* the future.
Young Doc: Great Scott!
[Doc faints]
Marty McFly: Doc! Doc! Doc! Oh, fantastic.
Marty McFly: I don't get it, Doc. I mean, how can all this be happening? It's like we're in Hell or something.
Doc: No, it's Hill Valley. Although I can't imagine Hell being much worse!
Marty McFly: [seeing a holographic ad for "Jaws 19"] Shark still looks fake.
[Jennifers from two different times confront one another]
Young Jennifer: I'm old!
Old Jennifer: I'm young!
Doc: They're taking her home, to your future home! We'll arrive shortly thereafter, get her out of there and go back to 1985.
Marty McFly: You mean, I'm gonna see where I live? I'm gonna see myself as an old man?
Doc: No, no, no Marty, that could result in a-
Doc: Great Scott! Jennifer could conceivably encounter her future self! The consequences of that could be disastrous!
Marty McFly: Doc, what do you mean?
Doc: I foresee two possibilities. One, coming face to face with herself 30 years older would put her into shock and she'd simply pass out. Or two, the encounter could create a time paradox, the results of which could cause a chain reaction that would unravel the very fabric of the space time continuum, and destroy the entire universe! Granted, that's a worse case scenario. The destruction might in fact be very localized, limited to merely our own galaxy.
Marty McFly: Well, that's a relief.
[Flying above Biff in 1955]
Marty McFly: There he is, Doc! Let's land on him, we'll cripple his car.
Doc: Marty, he's in a '46 Ford, we're in a DeLorean. He'd rip through us like we were tin foil.
Marty McFly: [Reading the newspaper from 2015] "Within two hours of his arrest, Martin McFly Jr. was tried, convicted and sentenced to fifteen years in the state penitentiary."? Within two hours?
Doc: The justice system works swiftly in the future now that they've abolished all lawyers.
[Doc and Marty in the time machine are about to depart from the Alternate 1985]
Doc: Time circuits on.
Marty McFly: What do you mean "Time Curcuits on"? Doc, we're not goin' back now!
Doc: Yep.
Marty McFly: Doc, What about Jennifer? What about Einstein? We can't just leave 'em here.
Doc: Don't worry, Marty. Assuming we succeed in our mission, this alternate 1985 will be changed back into the real 1985, instantaneously transforming around Jennifer and Einie. Jennifer and Einie will be fine, and they will have absolutely no memory of this horrible place.
Marty McFly: Doc... what if we don't succeed?
Doc: We *must* succeed.
Marty McFly: The almanac. Son of a bitch stole my idea! He must have been listening when I- It's my fault! The whole thing is my fault. If I hadn't bought that damn book, none of this would have ever happened.
Doc: Well, that's all in the past.
Marty McFly: You mean the future.
Doc: Whatever! It demonstrates precisely how time travel can be mis-used, and why the time machine must be destroyed, after we straighten all of this out.
Marty McFly: [on walkie-talkie to Doc] Doc! Biff's guys chased me into the gym and their gonna jump... me!
Doc: [on walkie talkie to Marty] Then get outta there!
Marty McFly: [on walkie-talkie] No, Doc. Not *me*, the *other* me, the one that's up on stage playing "Johnny B. Goode."!
Doc: [on walkie-talkie] Great Scott! Your other self will miss the lighening bolt, you won't get back to the future and we'll have a major paradox!
[Biff has just received his auto repair bill after crashing it into a manure truck]
Biff Tannen: 300 bucks? 300 bucks for a couple of dents? Now, hey, that's bullshit, Terry.
Terry: No, Biff, it was *horseshit*! The whole car was full of it. I had to pay old man Jones 80 bucks to haul it away!
Biff Tannen: Old Man Jones! Probably re-sold it too. Now, I oughtta get something for *that*!
Terry: You want to get something for it! We'll go inside, you can call Old Man Jones! If he wants to give you a refund, that's fine!
Doc: Marty! What in the name of Sir Isaac H. Newton happened here?
Marty McFly, Jr.: [in background watching TV] Oh great, the atrocity channel!
Marty McFly: [arriving in 1955] Oh, this is heavy, Doc. I mean, it's like I was just here yesterday.
Doc: You were here yesterday, Marty.
Biff Tannen: Hold on one second. Let's get this straight. Marty is *your* kid, not mine. And all the money in the world wouldn't do jack shit for that lazy bum!
Lorraine Baines: Stop it, Biff, just stop it!
Biff Tannen: Look at him. He's a butthead just like his old man was.
Lorraine Baines: Don't you dare speak that way about George! You're not even half the man he was.
[Biff throws her on the floor]
Old Biff: [watching the chase unfold in 2015] There's something very familiar about all this.
Biff Tannen: That's about as funny as a screen door on a battleship.
Marty McFly: [under his breath] It's "screen door on a submarine," you dork.
Marty McFly: Nice shot Doc! You're not gonna believe this, we gotta go back to 1955.
Doc: I don't believe it!
Marty McFly: 'Cubs win world series... against Miami'?
Old Terry: Yeah, it's something, huh? Who would've thought? 100 to 1 shot! I wish I could go back to the beginning of the season, put some money on the Cubs.
Marty McFly: I just meant that Miami- What did you just say?
Old Terry: I said I wish I could go back to the beginning of the season, put some money on the Cubbies!
Young Biff: Manure! I hate manure!
Iko 'Jitz' Fujitsu, Marty's Boss in 2015: [shouts] McFly!
Middle-Aged Marty: Fujitsu-san, Konnichiwa.
Iko 'Jitz' Fujitsu, Marty's Boss in 2015: McFly, I was monitoring that scan you just interfaced. You are *terminated*!
Middle-Aged Marty: Terminated? No, no, it wasn't my fault sir! It was Needles, Needles was behind the whole thing!
Iko 'Jitz' Fujitsu, Marty's Boss in 2015: And you cooperated!
Middle-Aged Marty: No, I didn't, ah, it was a sting operation.
Iko 'Jitz' Fujitsu, Marty's Boss in 2015: It was illegal, and you knew!
Middle-Aged Marty: I was - I was - I was setting him up.
Iko 'Jitz' Fujitsu, Marty's Boss in 2015: McFly, read my fax!
Middle-Aged Marty: No! Please! No! I cannot be fired, I'm fired! Oh!
[Fax comes out saying "YOU'RE FIRED!" on three different machines, In concern, Jennifer takes one of the copies]
Middle-Aged Marty: Oh, this is heavy.
[crumples a copy of the fax against his forehead]
Middle-Aged Marty: What am I gonna tell Jennifer?
Lorraine Baines: Dammit Biff, that's it. I'm leaving!
Biff Tannen: Oh, so go ahead. But think about this Lorraine, who's gonna pay for all your clothes, huh? And your jewelry, and your liquor? Who's gonna pay for your cosmetic surgery Lorraine?
Lorraine Baines: You were the one who wanted me to get these-these things! If you want 'em back, you can have em.
Biff Tannen: Look, Lorraine, you walk out that door and I won't only cut off you, I'll cut off your kids.
Lorraine Baines: You wouldn't!
Biff Tannen: Oh, wouldn't I? First, your daughter Linda, I'll cancel all her credit cards. She can settle her debts with the bank all by herself. Your idiot son Dave? I'll get his probation revoked. And as for Marty, well maybe you'd like to have all three of your kids behind bars just like your brother Joey. One big happy jailbird family.
Lorraine Baines: Alright Biff, you win. I'll stay.
Biff Tannen: [to Marty] As for you, I'll be back up here in an hour, so you better not be!
Young Doc: Nice talking to you. Maybe we'll bump into each other sometime again in the future.
Older Doc: Or in the past.
Marty McFly: What about the police, Biff? They're gonna match up the bullet with that gun.
Biff Tannen: Kid, I own the police! Besides, they couldn't match up the bullet that killed your old man.
Marty McFly: You son of a...
[Biff cocks the gun]
Biff Tannen: I suppose it's poetic justice - two McFlys with the same gun.
Marty McFly: [picks up a newspaper] 1985... it can't be...
[shotgun cocks behind him]
S. S. Strickland: Drop it!
[Marty drops the newspaper]
S. S. Strickland: So you're the son of a bitch who's been stealing my newspapers.
Marty McFly: Mr. Strickland! Mr. Strickland. It- it- it's me, sir. It's Marty!
S. S. Strickland: Who?
Marty McFly: [terrified] Marty McFly! Marty McFly! Don't you know me, sir? From school, sir!
S. S. Strickland: I've never seen you before in my life, but you look to me like a slacker!
Marty McFly: Yeah! That's right! That's right, I am a slacker! Don't you remember, you gave me detention last week!
S. S. Strickland: Last week? The school burned down six years ago! Now you got exactly three seconds to get off my porch with your nuts intact! One!
Marty McFly: [screams] Oh, please! Mr. Strickland! I just wanna know what the hell's going on here!
S. S. Strickland: Two!
Marty McFly: [covers groin] Ahhhhh!
[gang members in a truck round the corner]
Gang Member: Hey, Strickland!
[they do a drive-by]
Marty McFly: [covering his ears] Ah! Ah! Oh! Oh!
[jumps over porch]
S. S. Strickland: [fires two rounds] Eat lead, slackers!
Marty McFly: The answer's no, Griff.
Griff Tannen: No?
Marty McFly: Yeah, what are you deaf and stupid? I said "NO!"
Griff Tannen: What's wrong, McFly. Chicken?
Lorraine Baines: [frowns at a stuttering Marty] Are you all right?
Marty McFly: [stares at his mother's obviously enlarged breasts] I'm fine, I'm fine. It's just that you're so... you're so... big.
Television announcer: Broadcasting beautiful views 24 hours a day: you're tuned to the Scenery Channel.
[answering the phone]
Middle-Aged Marty: Hey, Needles.
Needles: So, did you take a look at that little business proposal of mine?
Middle-Aged Marty: I don't know, Needles.
Needles: What are you afraid of? If this thing works it'll solve all your financial problems.
Middle-Aged Marty: And if it doesn't work Needles, I could get fired! It's *illegal*! I mean, what if the Jitz is monitoring, huh?
Needles: The Jitz'll never find out!
Middle-Aged Marty: Oh, ha, ha.
Needles: Come on... Stick your card in the slot and I'll handle it. Unless you want everyone in the division to think you're *chicken*.
Middle-Aged Marty: [angrily] Nobody calls me 'chicken', Needles. Nobody!
Needles: All right, prove it.
Middle-Aged Marty: All right, all right Needles. Here's my card. Scan it, I'm in.
Needles: Thanks McFly, I'll see you at the plant tomorrow.
[Biff has chased Marty to the roof of a building]
Biff Tannen: Go ahead, kid! Jump! A suicide will be nice and neat.
Marty McFly: What if I don't?
[Biff points gun at Marty]
Biff Tannen: Lead poisoning.
Marty McFly: Tough break, kid. Must be rough bein' named after a complete butthead.
Marty McFly: What's that supposed to mean?
Marty McFly: [Biff knocks on Marty's head with his cane]
Marty McFly: Hello? Hello? Anybody home? Huh? Think, McFly! Think! Your old man, Mr. Loser?
Marty McFly: What?
Old Biff: That's right. Loser with a capital "L".
Marty McFly: Look, I-I happen to know George McFly is not a loser...
Old Biff: [interrupts him] I'm not talkin' about George McFly. I'm talkin' about his kid! Your old man, Marty McFly Sr.? The man who took his life and flushed it completely down the toilet.
Marty McFly: I did? I - I mean - I mean he did?
Marty McFly: Tell me about my future. I know I make it big, but do I become, like, a rich rock star?
Doc: Please Marty. No one should know too much about their destiny.
Biff Tannen: Where is he?
CPR Kid: Who?
Biff Tannen: Calvin Klein.
CPR Kid: Who?
Biff Tannen: The guy with the hat. Where is he?
CPR Kid: Oh he went that way. I think he took your wallet!
[to bystander]
CPR Kid: I think he took his wallet.
Marty McFly: [referring to Alternate 1985 Biff] How could he be your husband? How could you leave dad for him?
Old Lorraine: Leave dad? Marty, are you feeling all right?
Marty McFly: [shouting] No! No I'm not feeling all right! I don't understand one damn thing that's goin' on around here and why nobody can give me a simple straight answer!
Old Lorraine: Oh, they must have hit you over the head hard this time.
Marty McFly: Mom, I just wanna know one thing. Where's my father? Where's George McFly?
Old Lorraine: Marty... George... Your father is in the same place he's been for the past 12 years... Oak Park Cemetery.
Western Union Man: Kid, you all right? You need any help?
Marty McFly: There's only one man who can help me.
Old Biff: You always did have a way with women.
Young Biff: Get the hell out of my car, old man!
Old Biff: You wanna marry that girl, Biff? I can help make it happen.
Young Biff: Oh-oh, yeah, who are you, Miss Lonelyhearts?
Old Biff: Just get in the car, Butthead.
Young Biff: Who you callin' "butthead", Butthead?
[Old Biff starts the car]
Young Biff: How do you know how to do that? Nobody can start this car but me.
Old Biff: Just get in the car, Tannen. Today's your lucky day.
Marty McFly: Okay, everybody let's back up now, huh? Let's back up... let's everybody back up, give him a little bit of room, okay? A little bit of air. It's okay, I know CPR.
[to CPR Kid]
Marty McFly: I know CPR.
CPR Kid: What's CPR?
Biff Tannen: [coming to consciousness] YOU!
[Marty knocks out Biff]
Marty McFly: It's fine.
CPR Kid: Hey? Did you just take his wallet?
[to the crowd]
CPR Kid: He just took that guy's wallet!
Goldie Wilson III: [in TV Commercial] Hi friends, Goldie Wilson III for Wilson Hover Conversion Systems. You know, when my Grandpa was Mayor of Hill Valley, he had to worry about traffic problems. But now, you don't have to worry about traffic. I'll hover convert your old road car into a skyway flyer! For only $39,999.95. So come on down and see me Goldie Wilson III, at any one of our 29 convenient locations. Remember, keep 'em flying!
Skinhead: You're coming with us upstairs!
Marty McFly: [struggling to get free] Let me go!
Match: [grabbing Marty] Sonny, we can do this the *easy* way or the *hard* way!
[3-D hits Marty over the head]
Miscellaneous voice: The easy way.
Marty McFly: [showing the two boys how to play the shoot 'em up video game] I'll show you, kid. I'm a crack shot at this.
[shoots a perfect score with the electronic gun]
Video Game Boy #1: You mean you have to use your hands?
Video Game Boy #2: That's like a baby's toy!
Biff Tannen: [Calmly] Okay, have a seat.
[Marty just stands there]
Biff Tannen: [Angrily] SIT DOWN!
Marty McFly, Jr.: [re: the tiny pizza from Pizza Hut] Grandma, when it's ready, could you just shove it in my mouth?
Middle-Aged Marty: Don't you be a smart-ass!
Marty McFly, Jr.: [to young Jennifer] Hey Mom, nice pants.
Data: Hey McFly, you bojo, those boards don't work on water!
Whitey: Unless you've got POWER!
Biff Tannen Museum Narrator: Ladies and Gentlemen! Welcome to the Biff Tannen Museum! Dedicated to Hill Valley's #1 Citizen. And America's greatest living folk hero. The one and only Biff Tannen. Of course we've all heard the legend, but who is the man? Inside you will learn how Biff Tannen became one of the richest and most powerful men in America. Learn the amazing history of the Tannen family, starting with his great-grandfather, Buford 'Mad Dog' Tannen, fastest gun in the West. See Biff's humble beginnings and how a trip to the race track on his 21st Birthday made him a millionaire overnight. Share in the excitement of a fabulous winning streak that earned him the nickname "The Luckiest Man on Earth." Learn how Biff parlayed that lucky winning streak into the vast empire called Biffco. Discover how, in 1979, Biff successfully lobbied to legalize gambling and turned Hill Valley's dilapidated courthouse into a beautiful casino-hotel!
Biff Tannen: I just wanna say one thing! God Bless America.
Biff Tannen Museum Narrator: Meet the women who shared in his passion as he searched for true love. And relive Biff's happiest moment as in 1973, he realized his life long romantic dream by marrying his high school sweetheart, Lorraine Baines McFly.
Biff Tannen: Third times a charm.
[French kisses Lorraine]
Marty McFly: NO!
Marty McFly: I had a horrible nightmare. It was terrible.
Lorraine Baines: Well, you're safe and sound now. Back on the good old 27th floor.
Marty McFly: 27th floor?
[repeated line]
Doc: Great Scott!
Lorraine Baines: Biff Tannen, I wouldn't be your girl even if - even if you had a million dollars.
[first lines]
Young Jennifer: How 'bout a ride, mister?
Marty McFly: Jennifer! Oh, man, are you a sight for sore eyes; let me look at you.
Young Jennifer: Marty, you're acting like you haven't seen me in a week.
Marty McFly: I haven't.
Needles: Hey, the big M! How's it hanging, McFly?
Doc: Oh, and Marty, be careful around that Griff character. He's got a few short circuits in his bionic implants.
[after Marty pushes Griff]
Griff Tannen: Well! Since when did you become the physical type?
Doc: I went to a rejuvenation clinic and got a whole natural overhaul. They took out some wrinkles, did hair repair, changed the blood, added a good 30 to 40 years to my life. They also replaced my spleen and colon. What do you think?
Biff Tannen: You're supposed to be in Switzerland, you little son of a bitch!
Marty McFly: My father?
Biff Tannen: Did you get kicked out of another boarding school? Damn it, Lorraine, do you know how much perfectly good dough I blow on this no-good kid of yours, huh? On all three of them!
Lorraine Baines: What the hell do you care? We can afford it! The least we can do with all that money is provide a better life for our children!
Doc: Don't talk to anyone, don't touch anything, don't do anything, don't interact with anyone, and try not to look at anything.
[Marty and Doc have just arrived back in 1955]
Doc: Sometime today, old Biff will show up to give young Biff the Almanac. Above all, you must not interfere with that event. We must let Old Biff believe he succeeded, so that he'll leave 1955 and bring the DeLorean back to the future.
Marty McFly: Right.
Doc: Once Old Biff is gone, grab the Almanac anyway that you can. Remember, both of our futures depend on this.
Marty McFly: You don't have to remind me of that, Doc.
[after leaving Jennifer on her front porch swing in the Alternate 1985]
Marty McFly: I don't remember bars bein' on these windows...
Grandma Tannen: Biff, Biff, where are you goin' now?
Biff Tannen: I told you, grandma, I'm goin' to the dance.
Grandma Tannen: When you comin' home?
Biff Tannen: I'll get home, when I get home.
Grandma Tannen: Don't forget to turn off the garage lights!
Marty McFly: Are you two related?
Biff Tannen: [knocking on Marty's head] Hello? Hello? Anybody home? What do you think? Griff just called me Grandpa for his health?
S. S. Strickland: Is that liquor I smell Tannen?
Young Biff: Ahhh, I wouldn't know. I don't know what liquor smells like, cuz I'm too young to drink it.
Lorraine Baines: Biff, somebody already asked me to the dance.
Biff Tannen: Who? That bug George McFly?
Lorraine Baines: I'm going with Calvin Klein, okay?
Biff Tannen: Calvin Klein? No, it's not okay!
[repeated line]
Marty McFly: This is heavy.
Biff Tannen: Hey kid, say hello to your grandma for me.
Marty McFly, Jr.: [to the TV] Art off. OK, I want channels 18, 24, 63, 109, 87 and the weather channel.
Marty McFly, Jr.: Hey, hey! I'm walkin' here! I'm walkin' here!
'Ronald Reagan' Video Waiter: Welcome to the Cafe 80's, where it's always morning in America, even in the afternoo-noo-noon. Our special today is mesquite-grilled sushi...
'Ayatollah Khomeini' Video Waiter: [interrupts] You must have the hostage special!
'Ronald Reagan' Video Waiter: Cajun style.
'Ayatollah Khomeini' Video Waiter: You must have the hostage special.
[they keep repeating over each other, talking faster and faster]
Marty McFly: Hey, hey, hey, wait a minute, guys, hey, hey, hey guys! All I want is a Pepsi.
Officer Reese: Hilldale, nothing but a breeding ground for tranks, lobos and zipheads.
Officer Foley: Yeah, they outta tear this whole place down.
House Computer: [they use Jennifer's thumbprint to open the door] Welcome home, Jennifer.
Officer Reese: [Jennifer begins to awaken] You all right? You got a little tranked, but I think you can walk.
Officer Foley: Ma'am, you should reprogram, it's dangerous to enter without 'lights on'.
House Computer: Welcome home, Marty.
Middle-Aged Marty: Hey, hey, hey! Dad's home! That's right, he's home. Dad's home!
House Computer: Lord of the manor.
Middle-Aged Marty: Hello, hello!
House Computer: King of the castle.
Middle-Aged Marty: [Nobody answers] Hello? What the hell is this?
House Computer: Lithium mode on.
Middle-Aged Marty: That's better. Damn kids.
Old Lorraine: Aren't you and Jennifer getting along?
Middle-Aged Marty: Oh, yeah, great Mom. We're like a couple o' teenagers, ya know?
Marty McFly: Nobody calls me chicken.
Red the Bum: Crazy drunk pedestrians!
Griff Tannen: Gramps, what the hell am I paying you for?
Old Biff: Buttheads...
Biff Tannen: Hey butthead!
[Biff is walking down the street when a basketball suddenly rolls his way. He picks it up claiming it for himself]
Basketball Kids: [rightful owners come up] Give us our ball back. Give us our ball back.
Biff Tannen: Is this your ball?
Basketball Kids: Yes!
Biff Tannen: Do you want it back?
Basketball Kids: Yes!
Biff Tannen: [throws the basketball onto an upper balcony of a brown house] Well, go get it! Ha-ha!