Expressions convey what a person feels, so -- logically -- if a character has an expression permanently glued to their face, they must be ''feelin' it'' all the time. A Perpetual Expression, then, is a characterization device used to cue the audience of someone's nature. Very rarely do others remark upon their apparent facial paralysis, even if one's visage is stuck with a [[SlasherSmile rather]] [[KubrickStare unsettling]] [[HellishPupils look]].

As a side effect, when the character's expression ''does'' change, it is always important, and marks a big change to the character's normal demeanor.

Most common Perpetual Expressions include:
* EyesAlwaysShut
* PerpetualFrowner
* PerpetualSmiler
** CatSmile
** CheshireCatGrin
** SlasherSmile
* DullSurprise

Note that the accompanied characterization of these tropes should be left in their own article; this is merely an index for the varieties that are frequently ever-present on someone's face. Note however that many Perpetual Expressions [[JustForFun/XMeetsY mix and match]] various SmileTropes and EyeTropes.

Kind of the binary opposite of ExpressiveMask. Not quite FrozenFace, which is an actual face paralysis.

Mostly [[AnimationTropes Animation Trope]], but has occasionally been pulled off in LiveActionTV as well. Very common in VideoGames, especially in older ones due to their nature.