first, I'd like to say I have done this for a couple reasons. 1. Kyle is a great character, but it's difficult to make a movie based entirely around him. Anyway...
Green Lantern Corps: The last Lanterns
This film will take place mostly on Earth,and will involve the Ion entity attempting to restart the corps of its own volition, coming to the planet earth and creating lantern rings. Simon Baz, Jessica Cruz, and Kyle Rayner will all gain rings, and have to work together to find out what's happening to them.
Also, in the movie their rings slowly recharge by themselves without the need of a battery. This is because the rings are not normal rings, but they come from Ion, a limitless power source.
New Characters:
Kyle Rayner: A down on his luck graphic artist from earth. He lives in LA. Young and excited to be a hero. Knows next to nothing about the green lanterns though. Sensitive to other people's problems. Terrible at relationships Due to his artist back ground, his constructs are very large, imaginative and elaborate. The full extent of his imagination is on display with the power. He’ll create a samurai army, or a Mech Suit, or Cthulhu-Cat.
Simon Baz: Works at an automobile factory in Detroit. He’s smart enough to get a better job, but he prefers to keep his head down. He’s been caring for his sister financially since her husband was in a car accident.Doesn't trust people. He is a Muslim American. His constructs are mechanical, but he's a fast learner. He’ll see another lantern do something and try to do it, then make his own combinations of multiple things. He's very smart. He doesn't depend on his ring either. He’ll fight with his fists as soon as with the ring. Kyle is the strongest with his ring, but Simon is strongest without it.
Jessica Cruz: A shut-in. Has severe anxiety. Can't even leave her house. At 1st glance literally the worst choice for a green lantern in history. But, she has an inner strength. It's hard to get her ring going, making constructs, but once she starts she can make some great stuff. She mostly has fun with it. She makes the first stuff that comes into her head, or the most interesting.
Major Zmeck: a minor villain. Right hand to Amanda Waller. Leading the strike forces against the lanterns. Has some sadistic tendencies. May return in a later film as: Major Force.
Atrocitus: A hulking Sinestro corps member. Mute due to a missing tongue. Previously seen in the background in other films. Carnivorous and a brutal fighter.
Romat Ru: Was once a serial killer from Tomar Re’s world. Sent to prison by Tomar, but broken out by a Sinestro ring. He's the creepy, tall, and spindly type of killer. A Sweeney Todd type. Previously seen in the background in other films. His constructs are mostly bladed weapons.
Karu-Sil: A creepy figure. Reminiscent of some Japanese urban legends. She's a maniacal sadist. Constantly surrounded by three energy constructs of wolf creatures with a personal connection to her. They do her fighting for her. They are the only things she cares for.
We begin in the woods, where a group of hunters(Jessica Cruz and friends) are hiking through the forest. The stumble upon a mob killing, and they’re captured and executed, except for Jessica, who runs away in fear as her friends die behind her. She keeps running,never stops running.
We move to LA where we see a day in Kyle’s life. He works on some art at home. He's going around town, trying to sell a concept for a graphic novel he wrote. He hears about Superman saving some people in a mountain climbing accident in Hollywood. He gets a call from his ex Alexandra Dewitt, who works as a photographer in a magazine and might be able to get him a job as a political cartoonist. He declines, as that's not his dream, and leaves, passing through a back alley behind the bar to find an energy space Koi(Ion) floating over a homeless man. Ion shoots a ring at him, out of its own body, and it attaches to Kyle.
Meanwhile, in Detroit, Simon Baz is getting off of work at the factory. It's apparent he's very intelligent, and much smarter than others in the same job. He returns home, to his sister, who he's been supporting along with her son after her husband was in a car accident that left him comatose. The next day he returns to work to find he's been payed off. He tries to find a new job, but nobody's hiring. He's angry.
Kyle returns to Alex in the club, and he reveals the ring. He only has basic knowledge of Green Lantern( he thinks there's two of them, and only knows about them because of the Justice league. He's more knowledgeable on some of the dceu more famous heroes like Superman or at this point Wonder Woman) She, working in news, knows more, and explains the concept of Green Lanterns gained from various interviews and stories. Hal attempts to learn how to use his ring, and eventually is able to create constructs like the characters in his art.
Meanwhile, the government has been tracking the energy signatures of Green Lantern rings under Amanda Waller's command, and has recently detected Ion on Earth. They don't know what it is, just that it's the same type of energy as green lantern rings, just much more powerful. They also know that Kyle Rayner as a ring now, and are surveilling him.
Meanwhile in Detroit, near a heavily populated train station, a patrol car spots Simon Baz behaving suspiciously around a large windowless van. Simon gets in the car, and they follow. When he realizes police are chasing him, he attempts to escape, leading to a chase. We see Simon drive the car into the parking lot of his former factory work place, and run away as the car explodes, destroying a large portion of the fortunately empty factory. The police manage to corner Baz, when a green lantern ring flies onto him, and the bullets are blocked by its force field. Simon is shocked, but quickly learns how to use the ring, escaping the police.
Kyle tries to decide what to do next. Alex suggests he try and get into contact with the Justice League. Kyle is excited by the idea, when he hears from the news on the bars tv about a failed terror attack where the bomber escaped using a green lantern ring. They realize it must be a malfunctioning ring, and Kyle decides to present himself to the world as a new hero by catching the guy.
Kyle discovers Simon hiding out in an abandoned building, after learning how to ask his ring questions and using it to find Simon. They fight. Simon at first reluctant but becoming angry. Kyle trying and failing to be the stereotypical hero while confusing Simon with his bizarre constructs. Simon eventually wins(punched Kyle in the face) and gets ready to leave, first telling Kyle he’s not a terrorist, he was just in the wrong place at the wrong time. He needed money to help his sister and was trying to steal a car to sell. The car had a bomb in it, so he drove it to somewhere he knew was closed at the time without any people so it would go off safely. He has no idea who the van belonged to. He tells Kyle not to chase after him.
Then, government agents attack, using alien technology gained from the Krolotean ship to suck out their power rings energy. (Manhunter head) Lyle and Simon are both captured, taken to a black site, and interrogated. Their rings are studied, and scientists remove them. They eventually meet Amanda Waller, who interrogated them on if they know of any other Green Lanterns on Earth, what's happening in space, why a ring chose Simon Baz, are either of them affiliated with the government of Bialya, and if a hostile takeover of earth's government is planned.
Meanwhile, the Sinestro Corps members Arkillo, Karu-Sil, and Romat-Ru arrive on earth. The three have been sent to this planet to look for Ion then contact the rest of the Sinestro corps to capture Ion before he can create new lanterns. Sinestro wants to establish his corps as the new law in the Galaxy, and doesn't want competition. The Sinestro corps members split up to search for Ion.
Back with Kyle and Simon, things eventually turn from bad cop routines to good cop, as they are allowed out of their cells, shown alien technology, such as an alien radio taken from the Zamaron ship. They haven't translated much, but it seems from what they've learned something happened in space and the green lanterns are gone now. Simon manages to steal a gun from a guard and take Waller hostage, giving Kyle the opportunity to get the rings. Simon is stabbed by Waller, but they both escape. During the escape try discover that Waller has men ready to capture a third earth green lantern. Simon keeps his gun. He wants protection in case the ring is drained again.
The Sinestro Corps members on earth have discovered using their rings to scan for green energy that Ion is no longer on Earth, but he has left green lantern rings. Romat Ru sends out a message to the rest of the corps to search For Ion in space, and that they will kill the new green lanterns.
Kyle and Simon are now both fugitives. According to reports given to the media by Waller, Simon is a terrorist/ evil green lantern supervillain, and Kyle is aiding him. We get to see them being fugitives, trying to avoid getting made while getting food from a convenience store. Kyle learns from his ring the third green lantern is in Portland, Oregon. Kyle tells Simon what he knows about the lantern rings, which isn't much. He explains how the rings chose them because they have great willpower.
Kyle develops a plan. After they find the next lantern, they are going to find the Justice League. They're inexperienced, they have no idea what to do, and they need help. Simon disagrees with this plan. He thinks it's a bad idea and wants to go into hiding, but goes with it for now. While at the convenience store/gas station, they are attacked by Arkillo, and discover their rings are not working against the color yellow. Arkillo kills the gas station clerk. They manage to escape by blowing up the gas station with Arkillo inside.
After having caught an alien monster, and witnessing the death of the clerk, Kyle begins freaking out. He wanted to be a hero, but now he realizes the horror and near death that comes with it. Simon gives him a pep talk using the words Kyle gave earlier, and tells him that they need to find the third lantern, as the danger is even greater for he/her than before.
At the government blacksite, Amanda Waller plans her next move. Kyle and Simon know nothing about the power they have, so a shoot to kill order is given. All they need are the rings. With the green lantern corps gone, as long as the Justice League doesn't find out, Waller can do whatever she wants. She contemplated sending Task Force X to the site of the third lantern, where she’s pretty sure the other two are going, but decide against it. The official story will be a government raid to catch the lanterns. The soldiers prepare, equipping themselves with Krolotean technology. Then Romat Ru and Karu-Sil attack. They kill dozens of soldiers, than discover the green energy they detected was from a Manhunter head. Before leaving, they discover a security guard watching doomsday preppers on his break. This is a world of great fear. The Sinestro corps should take the planet over after the green lanterns are killed. They leave to go meet with Arkillo and find the Lanterns.
Kyle and Simon arrive at the suburban home the third ring should be in. Lights are on, but no one answers the door, so they break in. They find a very freaked out Jessica Cruz, who tries to shoot them. She's disarmed, and Kyle and Simon explain they were both given green lantern rings. She shows got one too. They explain the government is hunting them, as are aliens, and Kyle’s plan. They need to get out of Portland now though, before Waller's men, or the alien that attacked them get there. But, Jessica refuses to leave, and begins to have a panic attack. It is revealed she has severe anxiety and hasn't left her home in 3 years.
The Sinestro corps members arrive in Jessica's neighborhood. People run screaming from them as they march to Jessica’s. This world is one of great fear. Simon and Kyle fight the aliens. Due to inexperience, and vulnerability to yellow as rookies, they are losing. Jessica’s house is blown up, she watches them losing in front of her. They will die like the others did. She puts on her ring and saves them, facing her fears. The three fight the aliens. Simon shoots Atrocitus in the face while his shield is temporarily down so he can eat Simon. In the aftermath of the battle, The Justice League arrives. They've been looking into Simon Baz, and determined he wasn't the bomber. They also know about Waller. The Green Lanterns are made official Justice League members. Waller gets off with a warning, she's too high up and influential in the government, and all documents related to the Green Lanterns have been burned. The Sinestro corps members are captured by Waller.
The Justice League heads to the Hand Funeral Home in Detroit, where the true bomber is. William Hand is working on bombs in the basement when the league arrives and captures him, bringing him to the police.
Later, Simon, Kyle, and Jessica have some group bonding at Simon's sister’s home, when Ganthet, the Indigo tribe, and the blue lanterns arrives with Ion. He explains they are the last of the lanterns, and are needed in space, or else the universe will be destroyed.
End Credits Scene: William Hand is in prison, when he begins hearing voices, and begins to see shadows move strangely. As time goes on, the lights in his cell behave strangely too, and dead insects return to life. The power shuts off, there's a gunshot. A zombie prison guard possessed by something arrives to speak to Hand. Nekron is here, and has plans for Hand.
DCEU references:
Justice league
Amanda Waller
Suicide Squad
Black hand
Major Force
The country ruled by the villainous Queen Bee is referenced
Its possible a certain evil ring from another dimension may possess Jessica someday if she sticks with the Justice League