We've all heard it before... literally. Some people know each other so well, they finish each other's sentences. The effect is usually a demonstration of how close the two people are— they're so familiar with one another, they even think alike.
Generally comes in two forms— the single line and the complex dialogue. The single line goes something like,
Bob: Where are my damn— Alice: Glasses? Check your head.
The complex dialogue is more elaborate:
Bob: Where are my damn— Alice: Glasses? Did you check your— Bob: Yes, my head is always the first place I look, thank you very much. Alice: Mom was right, I should never have married— Bob: "A forgetful lout like you," yeah, I know.
Closeness and familiarity aren't the only reason for this trope. Others include:
Alice: That sexy young farmer has an enormous— Bob: Potato gun!
Making a quick gag by having the finished sentence be nothing at all like what the first person was going to say.
Alice: Maybe we should— Bob: Tie a banana on its nose and conga under its legs! Alice: I was going to say call the police.
Showing that two people who don't know each other are thinking the same thing.
Alice: Maybe we should— Bob: Cross the streams— Alice: And reverse the polarity— Bob: To raise the deflector shields! Marry me.
And more!
This trait is often found in Creepy Twins, Single-Minded Twins, and Sickeningly Sweethearts, but hardly restricted to them— lovers, parents, siblings, friends, co-workers, enemies, even strangers can do this. And while we're at it, it doesn't have to be only two— loads of people can get in on the act, although it might start to stretch credibility. Also present as a way of showing that two characters are telepathic or are parts of a Hive Mind.
If the characters are built around this trope, it's a sign of a big problem when they don't finish each other's sentences. If one character is a psychic, expect the other to shout something like, "Get out of my head!" Or even if they aren't psychic, if it happens often enough.
A similar effect is having characters Finish Dialogue In Unison. Two Scenes, One Dialogue and Distant Duet have characters finishing each other's sentences without even being in the same scene. Compare Strange Minds Think Alike, Catchphrase Interruptus.
Examples:
open/close all folders
Anime and Manga
The twins Hikaru and Kaoru in Ouran High School Host Club do this sometimes. In Haruhi's Alice in Wonderland dream, they played the Cheshire Cat and appeared alternatingly from different sides, finishing each other's sentences as they talked to Haruhi.
Happens in the finale of Stellvia of the Universe between Richard James and Carl Hutter when the two are having a few drinks on a desolate space station deck. James raises a toast, starting with "To the future...", and Hutter completes the sentence instantly, in the same tone: "...of humanity!" This is especially poignant, considering how Hutter is a shape-shifting Starfish Alien in disguise... and James knows it.
While not the most typical example of twins, in Cardcaptor Sakura, Yue and Cerberus pick a climactic moment during the final judgment to suddenly start finishing each other's sentences—with multiple clauses, no less. In fact, despite their apparent hostility toward each other at the time, it becomes nearly impossible to distinguish exactly who is speaking at some points.
Gunslinger Girl. Cyborg technician Louis Duvalier has beautiful twin assistants who do this. They even move in unison.
Koizumi and Otani from Lovely Complex are so (unintentionally) good at this that they (again, unintentionally) become a comedy sensation at their school.
In the Scott Pilgrim books, Ken and Kyle Katayanagi often finish each other's sentences with their reasoning behind it being that they would always work together after Ramona cheated on them behind their backs. This was obviously not in the movie as the only line the Twins have in the film is "Hah!" during a fight sequence.
Fanfic
The Weasley Twins, from Harry Potter are not an example, even though they are popularly portrayed that way in Fan Fiction. They don't complete each other's sentences in the books; rather, one will follow the other with the next appropriate sentence - they do not share a single mind, but simply think very much alike.
The ideal is Lampshaded in Harry Potter and the Methods of Rationality, which features a sections focusing on the Twins, and indicating something magical is at work. They don't actually share one mind, but come to the same conclusions when they have the same information. When one of them thinks differently than the other, they both feel uncomfortable until they share what they know and snap back.
Film—Animation
The Fates from Disney's Hercules do this, most noticeably in their introduction, when they're giving Hades the prophecy.
Tweedle Dum and Tweedle Dee in Disney's Alice in Wonderland (but not in the original book).
In Stuart Little, Mr. and Mrs. Little do this so frequently that they panic when they don't. Stuart cutely lampshades this as he hears his future adoptive parents do this for the first time.
Field Marshal Von Kluck: We were able to dupe Dr. Forrest by posing as a humanitary organization, who planned to wipe out hunger, by ageing cheese faster.
Rigby Reardon: But when your father finally saw what they were doing...
Field Marshal Von Kluck: - he began to assemble lists of names of our agents...
Rigby Reardon: - and seemed about to go to the FBI.
Field Marshal Von Kluck: We were zerfore obliged to kidnap him, drug him ang bring him...
Rigby Reardon: - here! First faking his death so there'd be no further investigation.
Field Marshal Von Kluck: But vile testing ze mold on a small island nearby...
Rigby Reardon: - the cruise ship "Immer Essen" passed by. Some of the passengers saw the tiny island dissolve.
Field Marshal Von Kluck: Zey were zerfore labeled "enemies" because of what zey haf seen. We had Walter Neff cancel all further tours and our...
Rigby Reardon, Field Marshal Von Kluck: - friends systematically began to eliminate everyone who was on that cruise ship.
Field Marshal Von Kluck: Schweinehund!
Rigby Reardon: Jerk!
In Bridesmaids, the main character is talking to a smugly newlywed couple and asks where they went on their honeymoon. They both say, "Disney World," and then the wife adds, "Sorry, we finish each other's sentences," as if there was any way they weren't both going to say the same thing.
Literature
Robert A. Heinlein's Lapis Lazuli Long and Lorelei Lee Long are clone sisters who do this. They first appear in his novel Time Enough For Love and show up in his later novels.
There is a James Thurber short story about this, called "The Curb in the Sky," where the trope has harrowing consequences.
Harry and Hermione do this sometimes in Harry Potter, such as in Deathly Hallows when they discover what happened to Gryffindor's sword.
In Fanon, Single-Minded Twins Fred and George Weasley are often written as doing this. In the books it only happened a couple of times and was more like collaborative interrupting. The movies were much more guilty of playing this trope straight with them.
The twins Beltira and Belkira from the Belgariad and prequels.
"Belgarath, our brother," one of them said, "it's been such-" "-a terribly long time," the other finished.
"Beltira," Belgarath said. "Belkira." He dismounted and embraced the twins.
"Dearest little Polgara," one of them said then. "The Vale has been-" the other started.
"-empty without you," the second completed. He turned to his brother. "That was very poetic," he said admiringly.
"Thank you," the first replied modestly.
Also Danae and Sarabian in the Elenium by the same author.
'Right,' she agreed. 'Tamul skin tone would be better with-'
'But not red-red, though. More scarlet, perhaps even -'
'No. Maroon's too dark. It's a ball, not a-'
'We don't wear dark clothes at funerals. We wear -'
'Really? That's a very interesting notion. Why do you - ?'
'It's considered insulting to -'
'The dead? They don't really mind, Sarabian. They're busy someplace else.'
Danae, however, has the added advantage of being the goddess Aphrael, so her intellect would obviously surpass that of Sarabian's, as she says he is not so bad himself when he comments that she is a stimulating conversationalist.
This was one of the traits that gave Mash's 'Radar' O'Reilly his nickname, and one of the parts of the book faithfully translated into the subsequent film and television series.
A variant in the Starcraft novel Liberty's Crusade. Kerrigan, being a telepath, tends to finish other people's sentences out of habit, which annoys just about everyone else. When she's leaving for her totally-not-a-date with Raynor after the Antiga mission, Liberty's last bit of advice is "remember to let him finish his damn sentences".
In The Hunger Games, Wiress tends to trail off or just stop speaking abruptly in the middle of her sentences, at which point Beetee finishes them.
In Spindle's End by Robin McKinley, Rosie and her best friend Peony take this one step further.
You finish each other's sentences half the time — or sometimes, if you think no one else is listening, you don't bother to finish them because you both know what you were going to say.
Lampshaded in Artemis Fowl and the Opal Deception. Mervall and Descant are twins, which are very rare among fairies.
"We're thinking of writing a book, aren't we, Merv? All about how we..."
"Finish each other's sentences," completed Merv, though he knew it would cost him.
"Shut up, you utter imbecile," snapped Opal, shooting Merv a poisonous glare.
Reynolds and Claude's promotion interview in the penultimate chapter of The Pale King. Chris incredulously wonders how long they had to practice it.
The Judy Blume book Double Fudge features single-minded twins Flora and Fauna Hatcher, who do this constantly - much to Peter's annoyance.
The Force-Sensitive Tash Arranda in Galaxy of Fear often finds herself finishing people's sentences, whether she knows someone or not. Sometimes this and her other talents make her come off as a Creepy Child, but part of the time she doesn't even know she's doing it. It causes her some trouble in Eaten Alive, when Leia Organa starts introducing herself and Han immediately gets suspicious. She also sometimes does it deliberately, as in City of the Dead when she's annoyed at an Honest John's Dealership and is pleased by how easily she can keep it up, thinking that the pushy proprietor must be shallow.
Live Action TV
In Psych, Shawn and Gus do this all the time. When Gus pairs up with Lassiter, they start doing this as well. Hilariously subverted when Juliet and Shawn decide they can pull this off as well.
Juliet: "Well, we have a h—"
Shawn: "—Hamburger!"
Juliet: "—Hunch. What the hell?"
Shawn: "You made an H sound."
Juliet: [[[[Corpsing trying not to crack up]]]] "And you went with hamburger?"
[Later gets a callback when Gus and Shawn partner back up. More or less:]
Shawn: Wanna grab snacks?
Gus: You know that's right. How about—
Shawn and Gus: [triumphantly] "Hamburger!"
Played with in (something like) this exchange in Community:
Abed: I hope they're not twins. Twins freak me out. They always know what the other one is...
Troy: Thinking?
Abed: Yeah. And they're always finishing each others'—
Carter: Mike, you and Caitlin are in danger of becoming one of those couples that claim you're apart, but in reality you're...
Stuart: ...so close that you finish each other's sentences. And the problem with that is that people like that inevitably end up...
Carter: ...romantically involved.
A Monty Python's Flying Circus sketch had a housewife receive a visit from a doorman who helped her finish sentences by first finishing them for her, then starting them so that she'd have to finish them.
Another Python sketch had an interview show with the host interviewing three men: one who only said the beginnnings of words, one who said the middles, and one who said the ends. After each said their own version of "Good evening," he had them all say "Good evening" together.
Michael:That time I was going to say "sandwiches".
Jack and Ianto do this in Torchwood in Day One of Children of Earth
Jack: Persistent-
Ianto: Good sign.
Jack: Dogmatic-
Ianto: Always a plus.
Gwen: Oh, Christ, never work with a couple, you two talk like twins!
In Broken News, the newscasters for PVS News routinely complete each others' sentences, or even words.
Lampshaded by Brian in a season five episode of Queer As Folk after Justin has told him to stop being cynical:
Brian: I'm not being cynical, I'm being-
Justin: -realistic.
Brian: Do you mind if I finish my own sentences? I despise when couples do that.
Sheridan and Delenn in Babylon 5 do this a little.
Attempted in They Think It's All Over:
Rory: Gary and I have been working together for so long that we can actually...
(Long pause)
Gary: ...finish each others' sentences?
It happens so frequently on Castle between Castle and Beckett that fellow detectives overhearing their conversation had to Lampshade it:
Ryan: Do they know that they're finishing each other's sentences? Esposito: (just shakes his head)
Another time, Ryan asks if they practice doing it when he and Esposito aren't around.
Lanie: It's so cute when you guys do that.
NCIS Los Angeles has Nell annoying the hell out of everyone by doing this on her first episode. Characterization Marches On, though, and now she's just doing it to Eric. It's played for laughs, and incredibly cute. Other partners on the show tend to do this as well.
All over the place on NCIS. McGee/Abby, any partners, any time the field agents brief Gibbs, any time Gibbs gives orders and the others anticipate him . . .
Gem and Gemma from Power Rangers RPM do this habitually; they don't speak (or think) as individuals much if at all until Gemma gets a boyfriend. After that, while they show signs of not being a Hive Mind, but still do this frequently. Just not all the time.
In Star Trek: The Next Generation there is a whole race known as the Binars who talk this way because of their binary/pair based culture and biology.
Noah's Arc: Subverted in the movie where Noah and Wade seem to start to give the same answers to relationship questions, but end with completely different ones. This is the first major sign they're have deeper relationship issues.
A recurring sketch on The Two Ronnies featured Corbett's character trying to tell a story, and Barker's character attempting to finish his sentences and getting it wrong.
On The West Wing, Will Bailey and Kate Harper do this in front of C.J., while trying to hide the fact that they're a couple. Both lampshade how bad they are at it.
In the episode Sateda of Stargate Atlantis Teyla attempts to do this with Sheppard; however it takes her three guesses to figure out what he's saying, and at one point she offends him by saying he has no friends.
Sheppard: Look, Teyla... I'm not really good at, uh... actually, I'm... I'm terrible at expressing... I don't know what you'd call it, uh...
Teyla: Feelings?
Sheppard: Yeah, sure, okay. The point is, I don't really have good, uh...
Teyla: Social skills?
Sheppard: Well, that is why I enjoyed flying choppers in the most remote part of my world before all this craziness happened, but, uh, you should know, I don't have, uh...
Teyla: Friends?
Sheppard: No. I have friends.
Sheppard: You, Elizabeth, Ronon, Carson, even Rodney, are the closest thing I have to a...
In Boardwalk Empire, Esther Randolph and her assistant use this trope to great effect as an interrogation technique when trying to needle Ray Halloran for information. Halloran even makes a joke about the two of them being married (they're actually only sleeping with each other).
There are two main examples in Bruiser. In the sketches with the cops doing a documentary, Mitchell's cop often has to finish the more talkative cop's (played by Webb's) sentences after he blunders over a saying or description. This trope is also the whole point of a series of sketches starring Charlotte Hudson and Olivia Colman as two friends in a pub discussing their sex lives. They frequently finish each other's sentences, until Colman invariably goes just a little too far.
JAG: Jennifer Coates does this several times, after she replaced Tiner as the Admiral’s yeoman in season nine, and is a source of irritation to the Admiral.
General Melchett: "Leave me, well I appreciate that Darling."
Darling: "No sir, I don't want to go into battle..."
Melchett: Without me?"
Magazines
In a TV Week interview, Hamish Blake and Andy Lee were talking about their close friendship.
Andy: "We-"
Hamish: "-finish each other's sentences."
Andy: "I wasn't going to-"
Hamish: "-say that."
Andy: "Well done, you got that one."
Newspaper Comics
A Dilbertstrip features a guy who does that in a sinister way:
Dilbert: I think I should take...
Sentence Finisher: Money from orphans?
Dilbert: No. I mean, I need...
Sentence Finisher: A large sack and an alibi?
Dilbert: You keep finishing my sentences with...
Sentence Finisher: Uncanny accuracy?
Stand-up Comedy
This is a crucial part of the stand-up act of Randy and Jason Sklar, as they are identical twins with exactly the same voice who seem to run on the exact same wavelength at all times. They practically turn finishing each other's sentences into a zen artform.
One performance of Henry VI Part II has Suffolk dragged offstage and killed before delivering his last line, leaving it to be completed by the pirate captain, which adds a wonderful creepiness to the scene.
Suffolk: Great men oft die by vile bezonians: A Roman sworder and banditto slave Murther'd sweet Tully; Brutus' bastard hand Stabb'd Julius Caesar; savage islanders Pompey the Great; and Suffolk— (sound of an axe) Pirate: Dies by pirates.
Speaking of Shakespeare's Henry plays, in Henry IV, Part I, Prince Hal finishes Hotspur's dying speech for him:
Roger: Oh, the wax. It's— Mimi: Dripping. I like it, between my— Roger: Fingers.
In The Serpent, a dark version of the Adam and Evestory the Serpent manages to do this to itselfevery time it speaks. The Serpents' lines often also overlap words and start before the previous line finishes.
Fourth WC: Sometimes, when it's very quiet, I can hear them breathing.
In The Gondoliers by Gilbert and Sullivan, when Marco and Giuseppe agree to jointly become the King of Barataria, they announce this in a verse where each of them sings only every other bar. It works like this, with Marco's part in plain text and Giuseppe's in boldface:
Replying, we sing As one individual, As I find I'm a King, To my kingdom I bid you all. I'm aware you object To pavilions and palaces, But you'll find I respect Your Republican fallacies.
Video Games
Final Fantasy VIII has one between Quistis and Squall in the beginning of the game. Rinoa joins in once she gets to know Squall well enough.
Amita: Let's do our best together. Yuri: Today, tomorrow and the day after that! Amita: Our wishes are one! To once again make the planet green! Yuri: In order to achieve that dream- Amita: Yes! We'll go forth full of expectations! Kyrie:Those two really seem to get along with each other... Stern: Indeed.
Bio Shock Infinite has Robert and Rosalind Lutece, a pair of twins who have a tendency to do this. Lampshaded once:
Rosalind: Odd, isn't it? Robert: What's odd? Rosalind: The fact that we sometimes— Robert: —finish each other's sentences?
Web Animation
The Twins of Thermopylae from Girlchan In Paradise episode 3 do this, but end up subverting it:
Twin 1: Thank you... Twin 2: For saving us! Kenstar: So, what, do you guys, like, finish— Twin 1: Each other's... Twin 2: Sentences? Kenstar: Wow! That's pretty annoying. Twin 1: Yes. It's all because our grandma... (beat; Twin 1 nudges the other one) Kenstar: So... I guess we should— Twin 2: Oh! Uh, um... 'cause our grandma pampered us with plenty of gifts! Twin 1: That's not what I... Twin 2: Was going to say... (both twins get shot by Kotomaru)
Tina of Wapsi Square does this to just about everyone, though she has been wrong at least twice. However, on both of those occasions, the question that was actually being asked was not one that she necessarily wanted to answer, so it may have been intentional. She also predicts the orders of everyone who comes to her coffee shop.
Schlock Mercenary had Kaff Tagon and Jevee Ceeta scared (and Ennesby grinning) when they noticed this. This relationship didn't end well, though.
Web Original
In That Guy with the Glasses 3rd year anniversary special Suburban Knights, the two groups, on a quest to find a hidden treasure, in seperate locations, invoke this trope.
(Camera cuts to show they are right back where they started)
Parodied in The Nostalgia Critic's review of The Odd Life of Timothy Green. Constantly annoyed at how the lead couple can always perfectly complete each other's sentences, he imagines what it'd like to see a couple completely misinterpret them. Cue skit.