Verbal Backpedaling

""And then, after I overthrow this fool- Oh, hello! I didn't know you were there!""

- Dread Lord, War Craft 3

When a character is busy "thinking out loud", only to suddenly discover that someone else has has overheard details that should've remained secret, what do they do?

Come up with an impromptu explanation on the spot, and hope the other character is fooled. Did the Big Bad just gloat about how he's going to Take Over the World? No, that was just a chapter for that novella he's been writing on the side. Er... right?

Villains seem particularly prone to this (due to their penchant for Evil Gloating), especially if the Big Bad and his Dragon (or another Big Bad) don't get along well and one of them is secretly plotting to betray the other; but it can really occur with any character who is a little overconfident. For example, a Hero in the midst of a Badass Boast may accidentally reveal too much about their particular powers, giving their opponent information on how to defeat them.

But in most cases, their impromptu explanation is enough to drop the matter ... at least for now.

See also Bad Liar and Implausible Deniability; compare and contrast Digging Yourself Deeper, Right Behind Me and That Came Out Wrong.

Film
"Van Helsing: He called Dracula "master".
 * Became an Overly Long Gag in the Josie and The Pussycats movie.
 * Played with in Dracula Dead and Loving It. When Dracula leaves the ball with Mina, Renfield runs after him calling "Master! Master!... I mean... Mister! Mister!" Shortly afterward:

Jonathan: I thought he said "mister".

Van Helsing: That was only a ruse to fool the feeble-minded! No offense."

Theater

 * In Sweeney Todd: The Demon Barber of Fleet Street, when Judge Turpin first comes to Todd for a shave, he mentions that he is marrying his ward (unaware that she is actually Todd's daughter), and comments that she's "pretty as a rosebud." "Pretty as her mother," Todd adds, but covers with, "No, nothing," when the judge asks what he said.
 * In Richard Wagner's Siegfried, the dragon's blood acts as a reverse Truth Serum, allowing Siegfried (and the audience) to hear through Mime's lies. Several times, Mime lets his malicious intent slip, Siegfried questions him, he objects that he didn't say that, then continues in a soothing tone telling Siegfried You Have Outlived Your Usefulness.
 * In Casina by the Roman playwright Plautus, the old man wants to sleep with the slave girl Casina his son is in love with. The old man makes a deal with his own slave overseer to marry the girl to the overseer, and then keep the wedding night activities for himself. Throughout the play, whenever things go his way, he gloats that he will be with Casina tonight. He is invariably overheard, several times by his wife, and says, "Er, I mean my overseer!" Making this trope Older Than Feudalism.

Video Games
"Guybrush Threepwood: If I gave you your arm back, what would you do with it?
 * The Curse of Monkey Island has this exchange, with the hero staying in the room all the time but the villain can't help himself:

Murray, The Mighty Demonic Skull: I'd terrorize the south seas! I'd torture the living! I'd demolish the- Errr...

[Beat]

Murray: What I meant to say was, I'd use it to pet kittens.

Guybrush: Nope. You blew it.

Murray: Drat."

Web Animation

 * One of the hidden movies in Legendary Frog's Final Fantasy VII: All About Random Battles animation may count as this trope. In Yuffie Joins the Party Genki Girl Yuffie pulls this until the last "What?"

Western Animation
"Dr. D.: See? And you thought I was just making it up!"
 * While not evil, Sam does this in Cloudy With a Chance of Meatballs by backtracking any time she says something smart, as part of her Obfuscating Stupidity routine. Subverted in that Flint doesn't immediately forget whatever she said before backtracking.
 * In the movie Grandma Got Ran Over By a Reindeer, Cousin Mel talks to herself about finding a way to sell Grandma's store for big bucks. She turns around to see the protagonist, Jake, who asks her what she said... Cue poorly thrown together excuse about her saying they'd need to sell a lot of fruitcake. Sure, that IS what she was helping with at the time, but still.
 * Somewhat of a subversion in Phineas and Ferb's Musical Cliptastic Countdown: Dr. Doofenschmirtz does this with his plan to control people using his MIND-CONTROL-INATOR. When he realizes that all of what he just said was on-camera, he quickly says, "I meant, 'Mimes control my gator!'" Cut to two mimes and an alligator.

"Dr. D.(pulls out a pie tray): "It's silver!""
 * Then he starts going off on his plan to Enslave the Tri-State Area... I mean... Engrave my pie-plate carrier!

"Cartman: You fools have no idea that I will never let you hurt the Wall-Mart.
 * In the South Park episode "Something Wall-Mart This Way Comes":

Kyle: * coming back on screen* I heard that!

Cartman: You heard what?

Kyle: You said we have no idea that you're never gonna let us hurt Wall-Mart.

Cartman: That's not what I said!"


 * In one episode of Adventures in Care-a-Lot, Grizzle is in disguise as Busybody Bear, spreading gossip to Cheer, Harmony, Trueheart, and Love-a-Lot in order to break up their band. Each time, the bear he's gossiping with expresses disbelief, and so, after hearing "That doesn't sound like something they would say," for the fourth time, he slips up and mutters, "Of course they would, you silly Care Bear," in annoyance. Realizing what he's done, he clears his throat and says, "Ah, I mean, that's what I 'heard.'"
 * Scudworth's constant muttering while the Board of Shadowy Figures plot the future of Clone High typically reveals his plan to create a clone-based theme park instead of an army. This tends to be perfectly audible to the Board.
 * Another non-evil example in the Family Guy episode "Boys Do Cry" has Peter repeatedly blabbing to a cop when they're supposed to be on the run, but avoids suspicion by backtracking every time Lois nudges him.