NOTE: This spoiler was submitted by Bryan.
Skyline opens with a panoramic shot of sky scrappers in a very expensive part of southern California. When the camera stops panning pretty blue balls of light start falling and landing in on the streets here and there. Cut to a bedroom, illuminated by the blue light, where Elaine and Jarrod are sleeping. The light wakes Elaine up and she moans about it being morning already, hops out of bed and goes to the bathroom to throw up. Jarrod's head is under the pillows so he's not seeing the blue light filtering in through the blinds.
The camera cuts to the living room over the aftermath of what must have been a pretty good party. Elaine goes back to bed but the blue light gets brighter and she shakes Jarrod awake. There's a scream from the living room. Ray is standing up looking out the balcony window at the blue light. Dark veins spread over his face and up his arms and shoulders and his eyes glow...
Cut to the interior of an airplane, 15 hours earlier, where Jarrod and Elaine are passengers on their way to see Jarrod's best friend Terry. Jarrod's really excited, messing around with some scrapbook or something. Cut to Terry driving a gray Ferrari, he hands the keys to the valet, takes the elevator up and kisses his wife, Candise. She complains about him being sweaty, it looks like he just got back from the gym. Candice gives Terry grief because Denise, Terry's personal assistant is there. Terry tells Candice that Denise is there working and goes off to shower. There's some conversation about it being Terry's birthday.
Back at the airport, Jarrod and Elaine get off the plane and find a driver is holding a sign that says "J-Rock." Jarrod says that's him and the couple hop in the back of Bently limo that drives them to Terry's super-plush condo complex. They go upstairs, and Terry greats them at the door. Introductions are made and an immediate trip to the pool. Candice tell's Terry to get her a cosmo, Terry and Jarrod walk to the bar and talk about Terry's success and about Jarrod moving from Brooklyn to LA to be part of it. They order to margarita's and go back to the pool. Candice is mad because he forgot her drink and sends Denise to get one for her. Obvious anomosity between Denise and Candice. Whle they're in the pool 4 military helicopters fly over the pool, Terry makes a joke about them getting ready for the trouble that will break out at his birthday party.
Flash forward, the party is in full effect. Terry introduces Ray to Jarrod and Elaine, Ray says Elaine is hot, and congratulates Jarrod on the new job and says he can't wait for him to move to LA. Elaine is obviously unaware of the job offer. She gets mad and storms off, Jarrod goes after her. Elaine tells him she's pregnant, instead of being happy Jarrod says he's not ready for it. As they're talking Denise walks through the bathroom, a few seconds later Terry comes out the same door. Busted. He looks sheepishly at Jarrod and Elaine. Elaine asks Jarrod if that's what the future holds.
In the main party room Ray is using a telescope that's hooked up to one of the tv's to spy on Terry's neighbors. The neighbor is on a sofa in a different condo, slouched down on a sofa and from the look on his face, he's about to cum from getting a blow job. He comes and another guy cuddles up next to him, and everyone at the party laughs in surprise.
There's a knock at the door and Oliver, the building super/night watch guy, tells Candice that the party is too loud. She asks who's complaining, the building is half empty, and Oliver says that half is asleep. She says, yeah, yeah, and Oliver walks off.
Back inside, everyone has gone home accept Ray and Denise. Denise stacks a claim to the sofa and Ray tries to get on her, and the sofa. She pushes him off and he sleeps on the floor. Day 1 flashes across the screen.
Back to the blue balls of light falling from the sky that opened the movie. The light fills the room and Denise yells at Ray to turn off the lights. He stands looking at it, out of the balcony door, veins pop up around his eyes, on his neck and upper body. He's in a trance, walks to the balcony door opens it and steps out onto the balcony. Then he vanishes. Denise screams and Jarrod tells Elaine to stay in the bedroom. He goes out to investigate and the blue light mesmerizes him. He stands there in a trance, longer than Ray, then starts to make his way towards the balcony, but Terry comes in and tackles him and tells Denise to shut the blinds.
Terry and Candice want to know what happened to Ray. Denise tells them, but they don't exactly believe her. Terry goes into the bedroom grabs his gun, Jarrod grabs his camera, and the pair head to the roof to see what's happening.
There are noises coming from the roof and Jarrod and Terry make there way down the hall towards the stairwell, the turn a corner and an old dude named Walt is standing there holding his dog. Terry tells Walt to go back to his condo and he and Jarrod go to the roof to see what's happening. They walk through the door and Jarrod lets it close behind them, trapping them on the roof. Terry complains about it, then they walk across a helipad to get a better look. Jarrod starts snapping pictures and using his zoom lens, and can see all the people drawn by the light being sucked up into giant space craft that have appeared from behind fog/clouds.
Smaller ships stream out of the large ships, and swim through the air trailing tentacles, they kind of look like the squiddies from the Matrix series. One of them spots Terry and Jarrod and heads towards them, the pair try to leave the roof but can't because the door is locked. Terry shots the door as the ship comes to get them. To no avail. The ship is on top of them blaring its blue light, when the door bursts open, it's Elaine. The blue light grabs her and she's standing there mesmerized. Jarrod grabs her and carries her back to the condo with Terry close behind. After a few minutes Elaine wakes up from trance.
They all gather around Jarrod's camera and look at the pictures of the people getting vacummed up into the spaceships. After looking at everything and realizing that smaller ships and other things are searching buildings for people, they decide that the only place the lights aren't landing is the water. So they come up with a plan to get to Terry's boat to escape. Terry tells them to pack food and water, while they do, he heads down to Walt's place.
At first it seems no one's home, Terry grabs Walt's Mercedes keys and he's about to leave the condo when Walt stands up holding his dog. Terry explains that their plan is to take Walt's car, get to the Marina and escape, but as the two men are talking, a squiddy ship approaches Walt's balcony, opens the door and starts probing. Walt and Terry hide behind the kitchen island, but the dog starts barking, Walt tries to quite it and the squiddy is about to go away when the dog breaks loose and runs around the corner. When Walt lunges after it he's grabbed and swallowed by the squiddy. Terry uses the opportunity to make a run for it, shooting wildly as he escapes.
While Terry is downstairs, Candice is looking at the pictures on the camera again. This time she finds pictures of Terry and Denise making out. She's not happy. When Terry gets back Candice gives him grief. He says we'll talk about it later. Elaine doesn't want to go. She thinks it would be better to just stay put, but Jarrod persuades her and the group heads down to the garage to escape.
Candice takes the keys to the Mercedes and she, Jarrod and Terry get in. Terry and Denise hop in the Ferrari. As they make their way towards the garage exit, they pass a husband and wife who are bickering. Jarrod rolls down the window and asks if they need help, they decline and so the Mercedes follows the Ferrari to the garage entrance. As soon as the Ferrari rolls out a giant, slimy gorilla looking alien smashes it's front claw down on the car. Then picks the car up and throws it to the ground. There's no sign of Denise, but Terry is thrown from the car. He manages to avoid being grabbed and runs back to the garage entrance where Jarrod is waiting to help him. Jarrod grabs Terry but the giant opens its hand and some sort of sticky tentacle thing shoots out and sticks to Terry. He is yanked away and stuffed into a hole in the alien's palm.
Jarrod gets back in the car and Candice puts the Benz in reverse to escape the alien that's trying to get them. As they drive through the garage another squiddy emerges and chases the group. After a minor crash, the group abandons the car and starts running towards the stairwell, joined by the husband and wife they saw earlier. They can't get the door open and as the alien closes in it grabs the husband and swallows him. As it moves towards the group an SUV rams the squiddy, smashing it against the wall. Oliver hops out of the car and opens the stairwell and the group starts to go in. The wife looks back and sees that her husband is still alive, they walk over to pull him out of the squiddy. Suddenly one of the tentacles grabs the husband by the head and rips his head and spine out of his body. For some reason the head and spin are glowing blue and the alien uses the husband's brain and spine to replace its own and then starts pursuing the group again.
They get into the stairwell but have to run across the pool area to get back to the safety of the building. The giant gorilla alien is waiting and pursues them as they dash between the columns. The wife suffers the same fate as Terry, a tentacle grab followed by palm stuffing. The rest of the group, go back to Terry's condo to hide and wait.
Oliver assumes a leadership position. Organizes a watch. Jarrod's long-term exposure to the blue light is changing him. The raised veins on his chest and abdomen are still there, and growing. Oliver notices but doesn't say anything.
One night they hear gun fire and look out the window to see people fighting back. A gorilla alien is chasing a pickup trip or hum-v with machine gun's blaring. The vehicle is smashed. And the gorilla alien stalks off.
Elaine notices the changes in Jarrod, also. She tells him that she was only exposed to the blue light for a few seconds and it knocked her out, so there's no way of knowing how long term exposure affected him. Terry ask her to remember how she felt when the light grabbed her, how at first she felt stronger, well, that's how he still feels.
A group of fighter planes fills the skies and starts attacking the big ships, they're escorting stealth bombers so that the military can launch a nuclear attack. The bomber gets through and delivers it's payload and one of the giant ships falls from the sky. Oliver is happy and tells them that now that we know how to kill them, help will come. Jarrod looks through the telescope and watches as the squiddies start to re-build the giant ship, just as the squiddy did with the husband's spine and brain. Jarrod tells Oliver we didn't kill it, we just pissed it off.
One of the window blinds breaks and Oliver and Candice are trying to cover the window with bedsheets and duct tape. Jarrod finds the water isn't working and decides that it's time to give Terry's plan to escape by boat another chance. Oliver and Candice are against it. Jarrod convinces Elaine to go with him by telling her that with the aliens and the radiation from the nuclear attack, it's not safe to stay. Oliver tells Jarrod that he's noticed the veins and isn't sure who's side Jarrod is on. When Oliver tries to stop him from leaving with Elaine, Jarrod grabs him by the throat and lefts him off the ground, the blue-light vein pattern appears around his eyes and on his arms as he manhandles Oliver. He throws oliver aside and walks over to Elaine, caresses her face and tells her that nothing has changed, it's still him.
Jarrod and Elaine see soldiers on the roof and decide to go and try to get help. While they make their way to the roof Candice is using the telescope and the veins start to appear on her hands and face. She walks to the balcony, blue light, and she is taken.
Oliver stands behind the kitchen island and turns on the gas burners on the stove and grabs the lighter, waiting for the squiddy to take him. When it comes for him, the lighter won't light and he grabs a knife and tries to find the tentacles off, but he's caught and dragged towards the window.
Jarrod and Elaine are on the roof, they approach the soldiers who tell them to keep away, The soldiers are trying to kill a gorilla alien but not having much luck. A helicopter approaches the roof and Jarrod and Elaine think they'll be saved but the gorilla alien shoots out tentacles and grabs the helicopter causing it to crash. Jarrod and Elaine decide the only way off the roof is to use the window cleaners scaffold. They walk towards it but a gorilla alien appears. A jet fighter comes into the scene and attacks the gorilla, but it gets too close and ends up crashing, it skips across the roof, crashes in to the gorilla alien, and blows up.
Oliver manages to stab the tentacle with a butcher knife and momentarily escapes, but as he's crawling across the floor another tentacle grabs him. He spots the lighter, rolls over onto his back and curses at the alien as he lights the lighter. There's an explosion that rocks the building and grabs Jarrod and Elaine's attention.
Jarrod and Elaine try to make it to the scaffold but a squiddy pursues them. First Jarrod fights it, he's subdued and Elaine uses an axe to brain it. It repairs itself and attacks Elaine, Jarrod comes to her rescue. Jarrod is injured and can't move. He tells Elaine to leave him, but she won't. The blue light shines down on them and they get sucked up into a ship passing over head, kissing as they twirl through the air.
Inside the ship we see what the aliens do with us. Tentacles are harvesting brains and spines and discarding the headless bodies. The brains and spines glow blue and are feed into an alien/machine that processes the brains so that they can power the gorilla aliens.
Elaine wakes in pool of bodies and slime and starts to crawl away from the harvester. She sees Jarrod and calls out to him, but the harvester grabs him, rips his head and spine off, and discards his body. But instead of glowing blue like the others, Jarrod's brain and spine are glowing red. The harvester doesn't seem to notice and feeds it into the alien/machine. The gorilla alien that receives it staggers and rubs it's head, the blue and red light seem to fight just below the skin.
The harvester grabs Elaine, scans her body and when it discovers she's pregnant transfers her to another room. There's another lady, presumably pregnant, screaming while being examined by the aliens. Elaine starts to scream as she's examined. A gorilla alien lumbers into the room. but instead of the tell-tale blue glowing eyes, its eyes are glowing red. it rips the harvester/examiner apart and rescues Elaine. She's freaked out when the red-eyed alien lumbers towards her, but the alien covers her belly and we can hear the babies heartbeat. The red-eyed alien caresses Elaine's face, the way Jarrod once had, and she recognizes him and screams his name.
A couple of still shots of the red-eyed alien carrying Elaine away and fighting harvesters and blue-aliens as the credits roll.