If you were somewhere else, then you won't have to die.'
I spoke not a word, 'though it meant my life.
For I'd been in the arms of my best friend's wife."
- In the anime Love Hina, the episode "The Case of the Missing Hinata Apartment Money: A Mystery", Narusegawa Naru refuses to let the other residents search her room for the missing money and later grabs the turtle, Tama-chan, when it is seen to have a piece of paper stuck to it (which is thought to possibly be a piece of one of the bills). Of course, it turns out that Naru was not the culprit; rather, she did not want the others to learn that she treasured a photo of herself and Keitaro, which she had been looking for and which was the paper stuck on Tama's shell.
- Detective Conan offers many many examples, and contains some subversions and aversions as well.
- Yoshihisa has one during the second half of Episode 7 of Kotoura-san. This is very much unlike him since he normally doesn't keep secrets at all. It's actually a Surprise Party for Haruka's birthday which is celebrated at the end of the episode. The fact that he managed to keep this away from Haruka for those two weeks was extremely Badass on his part!
- In Legally Blonde, Brooke Taylor Windham (a famous fitness instructor) is accused of murdering her wealthy husband. She actually does have a concrete and easily proven alibi, she was getting liposuction at the time of the murder, but the nature of said alibi would ruin her. Elle does manage to get her to reveal this, but due to a Delta Nu Oath, is sworn to secrecy. Thus she has to prove her clients innocence while withholding this piece of information. She eventually manages to out the real culprit via The Perry Mason Method, by pointing out a contradiction in her alibi, (And her hair).
- In 'Catch a Fire', Patrick Chamusso is held and tortured by the authorities. He is suspected of a bombing at a power plant, but cannot acquit himself because he spent the time with the mother of his secret 'illegitimate' son.
- In The Reader, Michael realizes that Hanna has made a series of strange, hasty moves, including working as a guard at Auschwitz, to conceal her illiteracy. Her continued efforts to do this result in her taking a far greater share of blame for an atrocity she was involved in than she should have, and those most responsible getting punished lightly.
- Almost always happens in Agatha Christie novels. Hercule Poirot sometimes comments that everyone has something to hide, and will therefore lie in an investigation.
- In Dorothy L. Sayers' Lord Peter Wimsey novel Clouds of Witness, the Duke was committing adultery when his sister's fiance committed suicide. The other woman was married to a vindictively jealous man, making her eventual decision to testify a serious danger, and also giving the Duke a motive to kill the dead man. Fortunately, Lord Peter manages to locate the dead man's suicide note, and the jealous husband's attempt to kill her results in his accidental death.
- In Have His Carcase, a boat was off shore when Harriet found the body. The owner was surly and obstructive, and his grandson had gone off to Ireland. When they had constructed several theories involving this boat, the grandson reappeared and explained that he and his grandfather had been poaching on another fisherman's lobster pots.
- In Whose Body?, the man in whose apartment the body was found eventually reveals his alibi: he had been persuaded to go to a nightclub.
- In Charles Dickens's A Tale of Two Cities, Charles Darnay refused to reveal even at his trial for treason that he is searching for the child of a family his father wronged.
- Gintaro Aono in Murder on the Leviathan has a Big Secret... which is that he is a doctor and not a soldier, much to his shame. The other characters are European and most of them don't understand that this might be why he was hiding that, making him seem so much more suspicious. Likewise with some of the other suspects.
- In Elizabeth Gaskell's North and South, Margaret is seen at a train station at night with a man. She cannot explain that he was her brother, as he is wanted for treason and was not supposed to be in the country.
- In the Sherlock Holmes story "The Boscombe Valley Mystery" the main suspect refused to tell police what he had argued with his father about moments before he died: He was married and didn't want the woman he loved (who was in the courtroom) to know.
- In "The Man With the Twisted Lip", a beggar is caught as a suspect in murder. He keeps silent until Holmes deduces his Big Secret:the beggar is the supposed murder victim - apparently, it pays much better than regular work.
- In Harry Potter and the Chamber of Secrets, Percy acts suspiciously because he doesn't want anyone to find out about his girlfriend Penelope Clearwater.
- In Isaac Asimov's The Currents of Space, a man is accused of a crime. The man accusing has been Mind Raped by the criminal and only remembers that the latter used the accused one's name, and seeing the man towering over him. The suspect subverts the trope immediately by revealing his very well kept Big Secret - extremely short legs which make it physically impossible for him to tower over anyone.
- An episode of Boston Legal featured a case in which the Big Secret was that the man was reluctant to use his alibi of having been in bed with another man.
- In an episode of the fourth season of 24, James Hellar's suspected/interrogated son isn't in league with the terrorists after all... but he is guilty of attending an anti-war rally and of being gay.
- The Star Trek: Deep Space Nine episode "Dax" is a typical example, albeit with an atypical defendant.
- Star Trek: The Next Generation: "The Drumhead" features an example. After sabotage leads to an investigation of everyone on board the Enterprise, the investigator's chief suspect becomes Ensign Tarses. A young man of mixed human/Vulcan heritage, it becomes clear he's hiding something and the investigative team is convinced he's behind the sabotage. Unfortunately for everyone, especially Ensign Tarses, it turns out that he's completely innocent of involvement in the original crime. His Big Secret turns out to be that he lied about his heritage to avoid discrimination in Star Fleet: his heritage isn't Vulcan, it's Romulan.
- In an episode of The Practice, a friend of Bobby's (who is also a lawyer) is protecting a prostitute in a murder case. The prostitute has an alibi (she was with a client at the time), but the client doesn't want to be revealed. The truth is that the client was the lawyer himself, who is married.
- In any given episode of New Tricks, expect three or four of these to come tumbling out before the murderer of the week is rounded up.
- One particularly beautiful example: one episode revolves around the 1984 murder of a peace protestor outside a NATO military base during an anti-nuclear protest. This, naturally, led to a lot of Big Secrets being dug up about spies and military 'spooks', government moles planted within the peace organization to inform on and discredit them, and secret plans to sabotage the military base's communications system — and all of it revolves around a 'secret' that the victim apparently had. After all of this, what, then, was the Big Secret that got the victim killed? Turns out he was sleeping with the girlfriend of one of the other peace protestors.
- Every episode of House: Member of family gets sick. Cause unknown. History taken, however investigation reveals: a) she was taking drugs, and didn't tell anyone b) she was sleeping around c) and got pregnant d) AND an STD e) AND she's a dude. The clinic scenes, often a microcosm of the whole show, are this to the extreme: patient walks in with a sniffle, walks out with divorce papers.
- Season four of Dexter. Dexter didn't kill his wife, Rita, but he DID kill a whole lot of other people...
- Broadchurch: it would be easier to name the characters who do not have a secret to hide.
- The song "Long Black Veil" is about a man who is hanged for murder because he refuses to reveal his alibi — he was having an affair with his best friend's wife.
- The Gary Moore song "Over the Hills and Far Away" (covered more recently by Finnish band Nightwish) describes a similar situation — the main character is sent to prison for a robbery he didn't commit, because he'd spent the night in the arms of his best friend's wife and refuses to reveal the secret. Interestingly the reason he was convicted was because his pistol had been found at the scene, implying that someone knew about it and framed him knowing he wouldn't say it wasn't him.
- Commonly used in the Ace Attorney games, though Phoenix and Apollo usually manage to prove some point with the secret once it has been revealed.
- A often used trick is for the defendant to be an accomplice to the murder, either blackmailed or hoping you can get them off without them having to go to jail themselves.
- In one particularly brilliant subversion, Phoenix manages to get a suspect to reveal their Big Secret, to the surprise of the court...and then the Judge pretty much says So What, and Phoenix immediately flounders when he realizes that the Big Secret was entirely worthless.
- Scratches. On the backstory the former owner of the mansion, (where the game is set) was accused of murdering his wife since an eyewitness told that she saw him carrying her corpse to the yard; Since he died soon after and the mansion passed to his best friend, who was also a respected doctor, the police was left with no evidence and a lot of suspicion about their real secret: All the time he had his deformed son locked in the basement, who was the real culprit in his mother's death.
- Virtually every episode of Fillmore! has these come out at some point, usually just before the clue pointing to the actual culprit turns up. These ranged from a Book Dumb character turning out to actually be an A-student, to the suspected mascot-napper turning out to have pilfered a rival school's goat mascot.