False Start

The main character has always loved or lusted for another character on the show. He gets his courage up to go tell her. Music swells, he takes a breath...

And somehow the whole thing gets derailed. Either he chickens out, she asks him a question about this hot guy she's been chasing, or she runs off to go fight vampires, or someone else barges into the room and destroys the opportunity entirely.

This can be a highly effective writing technique for a couple of episodes, but the writers typically find that it's impossible to maintain forever. Eventually, the character will tell the object of his affections, and the plot will move on...or the viewers will.

Name comes from the American football term when one player on the team moves before the ball is in motion.

Compare to Will They or Won't They. See also Red Herring Twist.

Anime & Manga

 * Yuppie Couple Menko ("Miss Noodle") and Shiruo ("Mr. Soup") in Urusei Yatsura are eternally on the verge of declaring their love for each other when the current episode's lunacy literally runs them over.
 * Watanabe in Excel Saga runs into out-of-left-field calamities every time he tries to get somewhere with "Miss Ayasugi" (Hyatt).
 * The most devastating of which was, after they got engaged and are finally about to have sex, . This ends up driving Watanabe insane.
 * A random schoolboy in Rozen Maiden is constantly interrupted by the cast from confessing to Jun's sister Nori.
 * This happens to Momoka on Keroro Gunsou all the time.
 * Kaorin of Azumanga Daioh has this problem through the entire series. Any time she tried to work up the nerve to even talk to Sakaki, she fell to pieces in increasingly amusing and neurotic ways.
 * In Shakugan no Shana (at least in the second season), any movement towards resolving the Love Triangle is rudely interrupted by the sudden arrival of the next overpowering Big Bad.
 * Happens a few times in Ah My Goddess, usually thanks to Skuld providing the interruption.
 * One episode of Mahou Sensei Negima features this one in regards to Nodoka's feelings for Negi.
 * Happens to Miroku and Sango several times in Inuyasha, mostly because both of them are inveterate Moment Killers.
 * The anime To Love Ru does this a lot. in the first episode alone the main character tries to confess to his love interest and is stopped in order by a soccer ball to the head, a flower pot to the head, a garbage truck, a herd of rampaging elephants, and finally a crashing alien spaceship.
 * Pretty much what happened constantly in the second arc of Cardcaptor Sakura with
 * Also done with Touya and Yukito, with a few twists:
 * In D.N.Angel this happens to Daisuke when he tries to confess his love for Risa in the first anime episode. (In the manga he managed to tell her, but she flat-out rejected him.)
 * In Vandread, a nervous Hibiki gets out an "I like y--"/'omae ga su---' to Dita, before the attack alert sirens go off.
 * Ushio of Yu-Gi-Oh 5 Ds is smitten with his lovely co-worker Mikage, but the moment he chose to make his feelings known to her unfortunately turned out to be the moment when she was having a rather intense conversation with Jack Atlas, which made it clear that she was in love with him. Either because Ushio knows that he can't compete with the younger, more glamorous, and better-looking Jack, or because he just wants her to be happy, he drops the attempt and apparently never works up the courage to try again.
 * Happens to Kosuda a few times in B Gata H Kei, including having getting his head caught in the door of a departing train while trying to confess his feelings to protagonist Yamada.
 * In Hayate the Combat Butler, Hinagiku asks Hayate how he feels for Athena. While he's struggling to try and figure out his feelings, she decides to try confessing, which he interrupts with the answer to the question, causing her for forget what she was about to say.

Film -- Live Action

 * Back to The Future
 * George McFly with Lorraine Baines in 1955 before they're married.
 * Pretty much what Bedazzled is built around - very early on we see Stanley screwing up the courage to ask Margaret out, and then folding. When the Devil offers him seven wishes, he uses them all trying (and failing) to create a relationship with her.

Live Action TV

 * See early Friends and Ross' unrequited love for Rachel.
 * Early Buffy the Vampire Slayer was full of False Starts.
 * Frasier pushed this trope about as far as possible with Niles. For several seasons, Niles struggles between lusting after Daphne and keeping his composure as she remains seemingly oblivious. The sheer number and intensity of the false starts is staggering, including several completely legitimate proclamations of love that are mistaken for something else. Most viewers agree that these were done well enough and kept far enough apart for the whole thing to work very well.
 * Happens a lot between Sam Tyler and Annie Cartwright in Life On Mars;
 * Happens to Chase a few times in "Zoey 101": he first tries to tell Zoey on a date (in which she shows up with her roommates, thinking it was just a friendly hangout), then he tries to tell her by sending her a text message only to have Zoey's phone get left by a fountain and fall in.
 * A variation appears on Gossip Girl. Chuck and Blair are both well aware that the other one loves them, but both refuse to date the other until s/he says those words out loud. Eventually Blair decides to say those words to Chuck but right before she meets up with him Dan tells her she's crazy if she thinks anything good can come out of saying those words to Chuck Bass. So she ends up chickening out, Chuck gets really mad and by the end of the episode they both agree that while the feelings between them are real they shouldn't be together at present.
 * Happens quite a few times in Psych between Shawn and Juliet. In one season finale, the almost kiss becomes "close talking" as they have a full conversation with their lips a few centimeters apart. Then there was the time when Juliet went to ask him out but he was on a date with another girl. In another episode, Shawn goes off on a tangent about cereal boxes and toys until Lassiter comes in.
 * To be fair, in that last example, the cereal box toys conversation was directly related to their situation, he just went on a little too long.
 * And then there was the
 * In the Alias season 2 episode "The Counteragent," Vaughn pursues Sydney after a tender moment is interrupted; however, Sydney is nowhere to be found.
 * Danny and Lindsay on CSI: NY;their romance was interrupted at first by Lindsay's trouble dealing with her turbulent past.

Web Comics

 * Turned Up to Eleven in Sam Logan's guest strip for Questionable Content.
 * Peanut of Housepets attempts to confess his feelings to his long-time friend Grape by presenting her with a dead chicken (on the advice of another dog) as a token of affection; before he gets the chance, however, he overhears her on the phone arranging a date with another guy. Ouch.

Western Animation

 * Used so much in Codename Kids Next Door for Numbuh Four's crush on Numbuh Three that even most shippers got tired of it.
 * And Numbah Three's Obfuscating Stupidity definitely didn't help matters.
 * Avatar: The Last Airbender uses it a couple of times. The most noticeable example is The Earth King, when Sokka interrupts Aang's confession.
 * Danny Phantom had Danny trying to ask his crush Paulina out to the dance, but Dash interrupts him by violently shoving him into a locker. He succeeds afterward through a magical pendent (though he didn't know it was magical at the time).
 * Code Lyoko actually has an episode with this title. Jérémie has finally brought his beloved Aelita into the real world...only to find out she has to return back to her virtual one, for the moment at least.