The humans and the aliens (Dracs) have been at war (in space) for some time now. There's a great deal of prejudice between them, and the humans think of the Dracs as "lizards" and some worse terms.
Then this one human, Willis Davidge (Dennis Quaid), shoots down a Drac ship, and both ships crash-land on a dangerous planet. Davidge's co-pilot dies and he's left to fend for himself. Then, while trying to get revenge on the Drac, he ends up getting captured instead.
The Drac, whose name, Jeriba Shigan (Louis Gossett, Jr.), gets shortened to "Jerry" for the film, forces Davidge to slave away at building shelter and such, as he managed to hang onto his sidearm. But when the danger from deadly terrain, storms and predators gets to be too much, Jerry and Davidge end up working together, and then becoming friends.
Then Davidge decides to head out and see if there's any chance of them being rescued, but Jerry won't come with him. A good thing, possibly, as Davidge finds good news in the form of a futuristic Pepsi can (evidence that humans have visited Fyrine IV) and bad news in the form of a Drac skull (evidence that the humans are illegal strip miners). Once Davidge gets back, he learns that Jerry is pregnant (turns out that Dracs can self-fertilize and have no control over the process). Sadly, something goes awry and Jerry dies in childbirth, so Davidge raises the kid, Zammis (ZAH-mees), by himself.
Either because the film studio thought that Viewers Are Morons or because films work better with a climax, the villainous humans return to set up their mine run using Dracs as slaves. Since Davidge didn't teach Zammis that some humans are evil bastards, Zammis quizzically wanders into the area and gets captured. Davidge tries to save him but is shot dead by a scenery-chewing slavedriver played by Brion James.
Or so it seems. Turns out his body is retrieved by a military scouter and brought back to the starbase where he once served. They're just about to give him a funeral (straight out the airlock) when he revives and starts mumbling in the Drac language while unconscious. His former comrades nurse him back to health, and he steals a ship and heads off to find Zammis.
In a final conflict with the evil miners, Davidge enlists the help of the Drac slaves, freeing them, taking out the overacting slavedriver and his cronies, and finding Zammis, for a moment like he was dead but then he rouses and says his Catchphrase from earlier, "Zammis get four, five?" (referring to how Dracs have only 3 digits on their hands while humans have 5).
Because Jerry taught Davidge his Drac lineage (something highly treasured in Drac culture), he is able to recite it to the elder council on Zammis' home world and formally introduce the young Drac to his own society. In honor of his actions, Willis Davidge's name is added to the Jeriba family line.
The novella and film provide examples of the following tropes:
- All Hail the Great God Mickey!: Alien Jeriba Shigan assumes that Mickey Mouse is a great spiritual figure.
- Arch-Enemy: Willis Davidge has Stubbs, an illegal mine owner who enslaved his adopted alien child.
- Autodoc: Used to heal Davidge after he got shot.
- Big Bad: Stubbs, the leader of the Scavengers.
- Bizarre Alien Reproduction: The Drac are parthenogenic, which means they self-fertilize. Watching Davidge helping the rather masculine Jeriba have a baby is more then a little surreal.
- Black Dude Dies First: The first casualty is Simpson, a black woman who's lead pilot of one of the fighters, when a Drac manages to get on her six and blast her to space dust. That Drac happens to be Jerry, and Davidge's attempted Roaring Rampage of Revenge is what kicks off the plot proper.
- Chekhov's Gun: The Fyrene Pit Fiend appears almost immediately after the crash, and repeatedly menaces both Davidge and Jerry. The turtle-like groundrunner, the Pit Fiend's first victim, also comes in very handly both as food and as a meteor shield.
- Conveniently Close Planet: Not only do they both crash on the nearby planet, but within walking distance of each others spacecraft.
- Crazy Cultural Comparison: Early in the relationship, Davidge quotes, "If at first you don't succeed, try, try again." Jerry thinks he must have learned this from "great Drac teacher, Shismar." Davidge responds he learned it from Mickey Mouse, and Jerry assumes he was a "great Earthman teacher." They also have this with Shismar's book that has its own version of "love your enemies" and when Davidge comments on hearing it before, Jerry replies of course, since it's universal truth.
- Curb-Stomp Battle: The beginning fighter scene starts out as this but turns ugly when the Drac ambush the Alert squadron. Also pretty much every time Davidge faces off against the slavemaster.
- Death World: Fyrene IV. If the predators and extremely powerful electrical storms don't get you, the periodic meteor showers will probably do the job.
- Death by Childbirth: How Jeriba dies.
- Deadpan Snarker: Jerry has quite a sarcastic streak at times. "Jerry, old buddy, where would you be without me?" "Back home."
- Disneyfication: The ending of the film is much more optimistic than the ultimately happy but rather more cynical ending of the original novella.
- Dies Wide Open: Joey, Davidge's co-pilot, fatally wounded in the collision with Jerry's ship.
- Double-Meaning Title: Caused by Executive Meddling. "Enemy mine" is a phrase referring to "the enemy of my enemy is my friend." The climax of the film also features a mine full of enemies.
- Due to the Dead: The funeral crew disposes of corpses in accordance with each stiff's beliefs. For example, before Davidge's corpus is brought to the checker on the conveyor belt leading to the airlock, the corpse of an agnostic soldier is unceremoniously dropped through the airlock ("No music."), with little more than a wreath and a "so long" from one of the young men to send him off, and before him a corpse of Christian denomination is airlocked with organ music with voiceover accompaniment and, yes, a wreath (though the music machine breaks down as the conveyor belt sends the corpses closer to the airlock). Davidge himself is about to be airlocked as "John Doe, Protestant" before one of the young men decides to try to take a possession off of him, resulting in Davidge letting him know rather violently that no, he isn't dead.
- Enemy Mine: The two main characters must join up against the elements to survive, in spite of being enemies. It's not the Trope Namer, however. The movie was named for the phrase that named the trope.
- Everyone Has Standards: Davidge isn't too fond of humans who slave Dracs, and is disgusted by the government who look the other way.
- Evil Is Hammy: If Brion James's villainous performance were any more hammy, several major religions would have to forbid watching it.
- Family-Unfriendly Death: Several of the slavers die short but very gruesome deaths like one being thrown by Davidge into an industrial grinder with a brief glimpse of his body being torn apart.
- Fantastic Racism
- Fire-Forged Friends: Davidge and Jeriba have to cooperate if they expect to survive at all.
- The Golden Rule: The aliens' holy book has a version of the quote. Davidge remarks that the Bible has a similar quote, and Jerry isn't surprised. "Truth is truth." It highlights how neither of them practiced this (being at war) until they were forced to as well.
- Honorary Uncle: Davidge. It loses "honorary" when his name is added to the line of Jeriba.
- Humans Are Bastards: The Dracs tend to think so. They claim that the humans are actually the aggressors in the war. But the humans believe otherwise.
Davidge: "A race of non-Human aliens called the Dracs were claiming squatters rights on some of the richest star systems in the Galaxy. Well, they weren't going to get it without a fight......"
- This is more or less inevitable, since the common folk on both sides have little to go on but propaganda intended to make them more willing to support the war effort. The Drac, however, claim the region being fought over on the basis that they were there first, by a wide margin, and the humans are upstart interlopers. The brief narration at the start indicates the Dracs seem to have the truth on their side.
- Humans Are Ugly: So says Jerry, at any rate."You... ugly... head."
Davidge: (Manly Tears) Do I?
- However, Jerry saves Davidge's life because he states that the Pit Beast is even uglier.
- Zammis says Davidge looks "terrible" after he's rescued.
Zammis: *crying* "I wish I was not a Drac!"Davidge: "Hey, hey... Now, as far as Dracs go, you are one good-lookin' kid!"
- Inverted prior to that. Zammis had been exclusively raised by Davidge, and grew up ashamed of himself for not looking "normal" like his uncle:
- Humanoid Aliens: The Drac have certain fundamental differences from human biology (most notably their reproductive cycle), but they're still bipeds with two arms and a head on top that does the talking.
- Idiot Ball: Davidge, at first. He hounds Jerry down and inflicts a fatal wound on his fighter with his blasters. What does Davidge do? Follow him right into the planet's atmosphere. When he sees Jerry ejecting, he just powers straight ahead, right on into Jerry's now-abandoned craft, causing the crash that kicks off the story proper. He doesn't do much better on the planet at first...did he not have an inkling that maybe the Drac escape capsule and/or sidearm would have security features to them to incapacitate potential ambushers?
- Mirrored Confrontation Shot
- Mood Whiplash:
- Davidge, chasing after a groundrunner, falls headlong into a familiar looking pit, cussing a blue streak. Slapstick soon turns to horror, though, when the resident Pit Fiend's tongue appears and begins seeking him out...
- An even more drastic one: the meditative sunset scene with Jerry and Davidge is interrupted by another lethal meteorite storm; they barely make it back to shelter, and amidst the continuous roar of the impacts around them, they're almost immediately at each others' throats...
- Mugging the Monster: Davidge attempts to sneak-attack both Jeriba (to steal his supplies) and the slavedriver (to rescue Zammis). To say the least, neither ends well.
- Narrator All Along: The narrator turns out to be the elder Drac in the slave camp.
- Nicknaming the Enemy: Dracs are called "lizards" by humans.
- One-Gender Race: There are no male Drac or female Drac, as each Drac is both male and female at the same time.
- Only Mostly Dead: Davidge survives being shot.
- Papa Wolf: Never mess with Zammis, ever.
- The Power of Friendship
- Pronoun Trouble: Jeriba is referred to as "it", rather than "he" or "she," because all Drac are hermaphrodites.
- Humans were calling Dracs "it" without knowing they were hermaphroditic, however, so it's more initially a case of Fantastic Racism.
- Recycled In Space: The novella and the film are Hell In The Pacific IN SPACE!
- Reptiles Are Abhorrent: Subverted — the Drac are loathed by humanity and personally by Davidge in the beginning, but Davidge becomes friends with Jerry, and ultimately raises his child.
- Revenge Before Reason: Davidge does it twice in quick succession
- When one of the human pilots gets shot by Jeriba, despite having malfunction of his own engine and against suggestions of the co-pilot, Willis goes on a chase after the Drac. This gets him and the alien stranded, while the co-pilot dies during the crash.
- Right after the crash, his very first decision is not to fend for own survival or do anything else - he heads straight to the crash site of the Drac's fighter to finish off the survivor.
- Shout-Out to Shakespeare: "Double, double, toil and trouble! For my little brother!"
- Super-Persistent Predator: Taken to an extreme by the Fyrene Pit Fiend. Having its tongue blasted off and the inside of its mouth scorched wasn't apparently enough - it deliberately followed them to their camp to stage an ambush. In an ironic twist, it also saves their lives, forcing them out of the shelter just as a rock formation falls on it and crushes it - and the Pit Fiend.
- Truly Single Parent: The drac parental lineage is truly linear, since they are self-fertilizing like some terrestrial reptiles. In the words of the novella, "Don't tell a drac to boff himself, because he probably will!"
- War is Hell: Par for the course for a Wolfgang Petersen film. It starts with the debris from a shot-up human fighter and the frozen body of the pilot, and gets worse from there. Highlighted by the atrocities that the human leaders conveniently ignore because they're at war.