Characters in a work of fiction experience limited sense data corresponding to the limitations of the medium
Alice walks into Bob's office late at night when the lights are off. Bob is sitting at his desk facing away from the door. Alice starts telling him about the Ancient Conspiracy she's uncovered, and urges him to come and help her. When he doesn't respond, she walks up to his desk and turns his chair around - only to recoil in horror when she discovers that he's dead, and has been for several days. But hold on - why didn't she notice the smell of his flesh rotting? This trope is when the characters in visual media seem not to possess the traditional five senses (sight, hearing, smell, touch and taste), instead limited solely to sight and hearing - because, naturally, the audience is only experiencing the work through these senses. It is most obvious in the case of characters seeming to be oblivious to smells that should logically be there (such as rotting flesh, as above), but it is not unusual to see characters not seeming to notice certain gustatory or tactile sensations even though they should be obvious. It can even happen with senses beyond the traditional five, with characters appearing oblivious to extremes of temperature (see Convection Schmonvection) etc. It is most commonly seen in film, television and video games, but other visual media such as theatre can be affected also (there is nothing stopping theatre directors simulating the smell of, for example, rotting bodies in their plays, but most do not, as the audience probably would not appreciate this dose of realism). Subtrope of Rule of Perception. Sister Trope to Behind the Black (when characters in a work of fiction can't see something because the audience can't).