!For characters who debuted in ''Star Trek: The Original Series'', see Characters.StarTrekTheOriginalSeries
!!Lieutenant Valeris (Kim Cattrall)
* [[GreenSkinnedSpaceBabe Green Blooded Space Babe]]
* SuckSessor: A variation, since aside from the whole bit about being a traitor and a murderer she's actually an extremely competent officer.
* SuspiciouslySimilarSubstitute: For Lt. Saavik from films II-IV, plus Commander Xon from the unmade ''Star Trek: Phase II'' TV series, in that they're both Vulcans who are set up to succeed Spock.
* TemptingFate: She suggests serving Romulan Ale during the meal with the Klingons, which given the underlying tensions between the two peoples and the extreme strength of Romulan Ale, goes over about as well as you'd expect. Of course, this is part of a XanatosGambit to make it later look like Kirk attacked Gorkon's ship in a moment of drunken rage.
* WhatCouldHaveBeen: If she ''had'' been Saavik as originally planned, rather then being made into the aforementioned Suspiciously Similar Substitute, it would have been a lot less obvious, and indeed rather shocking, who the traitor on the ''Enterprise'' was. As it is in the finished film, with her being the only new major character on the ''Enterprise''... Well, it isn't like they would have made Spock, Scotty, Uhura, or Chekov the traitor! Process of elimination really only left Valeris as the audience's only suspect.
!!General Chang (Creator/ChristopherPlummer)
* BaldOfEvil: He was supposed to have long hair, but Christopher Plummer had liked his bald appearance, so Chang became bald..
* BigBad: He fills the role of the film's main bad guy, but he's really part of a BigBadEnsemble including Admiral Cartwright, Colonel West and the Romulan Ambassador.
* ChewingTheScenery: It's not enough that he's already a LargeHam. When reciting Creator/WilliamShakespeare he proceeds to shout it at the top of his lungs and ''spin in his captain's chair''.
* EvilCounterpart: A bald starship officer who quotes Shakespeare? Never head that one before.
* EyepatchOfPower: Bolted onto his skull, no less.
* FaceDeathWithDignity: Upon seeing the modified torpedo approaching his ship, he quietly says "To be, or not to be..."
* IncomingHam: He has an impossible to detect ship. Rather than simply unload on the ''Enterprise'' he decides to open a channel and [[IShallTauntYou announce himself.]]
--> I can see you, Kirk... Can you see me?
* '''LargeHam''': He quotes [[ShoutOutToShakespeare Shakespeare]] as a ''[[IShallTauntYou battle taunt.]]''
* ObiWanMoment: When he realizes that ''Enterprise's'' torpedo is homing in on his ship, he simply waits for it while quoting Shakespeare.
* WellIntentionedExtremist: The ''VideoGame/StarTrekKlingonAcademy'' video game gives a better, more detailed look at his motives; basically, he's an honorable conservative who genuinely fears Gorkon's moderate policies will lead their race to their doom.
* WorthyOpponent: Despite all his efforts to have Kirk framed and killed, he makes it clear that he holds him in the highest regards as a skilled and accomplished warrior.
!!Chancellor Gorkon (Creator/DavidWarner)
* FamousLastWords: To Captain Kirk. "Don't let it end [[ThisMeansWar this way]], Captain..."
* GenreSavvy: As soon as his ship is attacked, he demands that [[EvilChancellor General Chang]] be located.
* HonorBeforeReason: Many of his fellow Klingons were against his decision to present an olive branch to the Federation. It cost him his life.
* OurPresidentsAreDifferent: Chancellor Target and Chancellor Personable.
* ReasonableAuthorityFigure: While his hand was largely forced by the explosion of Praxis, ''Klingon Academy'' shows that he had wanted peace with the Federation before he originally became Chancellor.
* XMeetsY: Gorkon is UsefulNotes/AbrahamLincoln meets Mikhail Gorbachev as [[ProudWarriorRaceGuy a Klingon]].
!!Colonel Worf (Creator/MichaelDorn)
* [[IdenticalGrandson Identical Grandfather]]: Confirmed by WordOfGod to be the grandfather of his namesake in ''Series/StarTrekTheNextGeneration''. This, incidentally, makes Dorn one of only two people -- the other being Creator/MajelBarrett -- to appear on-screen in TOS, TNG and [=DS9=]-related works.
* SpannerInTheWorks: He persuades the judge at Kirk and [=McCoy=]'s trial to sentence them to exile on Rura Penthe rather than giving them the death penalty. It's subtle, but you can see that Chang is ''not'' pleased by this development, and it allows Kirk to escape and foil the conspiracy.