My fan-made story and cast for the upcoming Man Of Steel sequel.

This is my plot idea for MOS 2. Please give your opinions on it if you can.
 

We open with a flashback on Krypton, where Jor-El (Russell Crowe) is seen helping to broker a peace treaty with the Coluan and Martian people. A Coluan Zealot named Vril Dox (Zachary Quinto) attacks the treaty signing, attempting to assassinate the Martian and Coluan leaders, killing Martian warrior M'yrnn J'onzz in the process.

Jor-El attempts to reason with Vril Dox, with whom he was once friends, distracting him long enough for General Zod to subdue him. Vril Dox escapes using a cube-shaped object that transports him to a place unknown. 

After this escapade, Jor-El is seen comforting the family of M’yrnn J’onzz for their loss. A few days later, Jor-El says goodbye to his brother Zor-El, who plans to leave Krypton on a scout ship with his wife and several other explorers. An attack from a mysterious ship causes the scout ship to crash-land on Earth. 

In the present, one year after the formation of the Justice League, Superman has fully accepted his role as a protector of Earth and is beloved by the people. He is shown in Metropolis stopping a terrorist attack by Manchester Black (Andrew Garfield) and Vera Black (Natalie Dormer). Superman uses his heat vision to temporarily disable Manchester’s telepathy and has them both arrested. 

Lois is doing an article on the “new and improved Lexcorp”, which is which is now supposedly run by Eve Teschmacher with Lex Luthor behind bars. The company plans to unveil a new clean energy reactor for Metropolis at the end of the fortnight. 

Meanwhile, a CIA Operative named Detective Jones (David Oyelowo) is investigating the activity of Lexcorp. Jones visits Lex in prison, suspecting his company of capturing and experimenting on anonymous metahumans in order to sell them to Amanda Waller as new candidates for Task Force X. Luthor calmly denies this.

After Jones leaves, Luthor contacts Teschmacher, whom he orders to send out their beacon to the ship they have found. The ship arrives on the planet, landing on an uncharted island owned by Lexcorp. 

Jones later infiltrates Lexcorp and retrieves several files of metahumans, including files on the location of Clark Kent. Clark and Lois go to visit Martha, where they see her being interviewed by Jones. He and Clark talk outside, where Jones reveals that he knows of Clark’s identity as Superman. 

To Clark’s surprise, Jones reveals that he is truly J’onn J’onzz, the son of Martian hero M'yrnn J'onzz. He has travelled to Earth to ask Superman’s help to destroy an old enemy of Jor-El’s called the Brainiac. Clark remains curious, before J’onzz tells him of the captured metahumans, one of whom is a girl named Kara Danvers (Chloe Grace-Moretz) with powers similar to Superman’s. 

With help from Bruce Wayne, J’onzz and Clark find the facility and free the metahumans, bringing Kara to Superman’s newly established Fortress Of Solitude. Kara reveals that she has a Kryptonian command key, which Superman inserts into the Fortress computer. It contains a backup copy of the Jor-El AI, who reveals that Kara’s true name is Kara Zor-El, and that she is Clark’s cousin. 

Clark asks the AI about the Brainiac, and Jor-El’s AI tells his story. Vril Dox was a close friend of Jor-El’s and his lab partner, who helped him to design and construct the many creations he had built for Krypton. Dox, a Coluan, planned to build weapons with which to wipe out the Martians, but Jor-El decided to suggest a peace treaty between the warring peoples. Furious at this betrayal, Dox began to experiment on himself, earning the nickname Brainiac as his mind and body grew more powerful. 

After the foiled assassination attempt, Brainiac used a Mother Box to escape and build a new ship, with which he attacked Zor-El’s scout ship, killing both of Kara’s parents and causing them to crash on Earth. J’onzz reveals that Brainiac has invaded Mars and will come to earth to wipe out Jor-El’s bloodline. 

Luthor is removed from the prison and goes to the island, where he meets Brainiac. Brainiac reveals that he has given a gift to Luthor for his help: an anti-Kryptonian armor and Kryptonite Reactor. Luthor gratefully accepts this, giving Brainiac the coordinates to Smallville in exchange. 

As Clark and J’onzz research more about Brainiac, Kara is taught to control her powers with help from Clark and Diana Prince. Diana also teaches her how to program the coordinates of a Mother Box using the one from Themyscira. 

Clark takes Kara to Smallville to meet Lois and Martha, where they are ambushed by Brainiac. Brainiac mocks Superman, telling him that his father would be ashamed of what he has become. Kara furiously attacks Brainiac, accidentally bringing the fight to downtown Smallville and endangering the public. J’onzz arrives and helps to evacuate citizens and reduce damages as Clark and Kara fight Brainiac. 

Though Brainiac is strong enough to fight them both, his prolonged time away from his ship begins to weaken him, allowing Kara to overpower him. Kara fights violently and uncontrollably, nearly killing Brainiac before Superman stops her. Kara looks around to see the citizens running away in fear, before the military arrives and arrests her. Before Brainiac escapes, he secretly places a small parasite on Kara’s neck as she is captured. 

At a secret military facility, Superman and Johns attempt to reason with General Swanwick for her release, but Swanwick reluctantly refuses, stating that Kara is too unstable to be released. 

When Johns and Clark leave, Brainiac remotely activates the parasite on Kara’s neck, which takes over her body and causes her to lash out. During this, the possessed Kara kills several military staff including General Swanwick. The parasite deactivates and separates from Kara, allowing her to see the damage she was forced to cause before flying away. 

Superman and J’onzz find her at the Fortress, sitting in shame of her actions. Clark comforts her, telling her of how he felt the first time he killed someone. Inspired by his words, Kara decides to try again, now wearing a female-fitting version of the Kryptonian under-armour. 

J’onzz and Kara go to Lex and interrogate him, where he reveals that the clean energy reactor has been replaced with Brainiac’s Kryptonite reactor, and will explode to weaken both Superman and Kara, who now calls herself “Supergirl”. 

That night, Teschmacher unveils the reactor, before J’onzz and Superman arrive to deactivate it. Before they can do so, Luthor arrives, now wearing the anti-Kryptonian armour. He fights Superman, slashing him with a Kryptonite blade and blasting him with Kryptonite gas. Superman and J’onzz work in tandem to fight Luthor, and when Superman is knocked down, J’onzz tries to tear out the power source of the suit. 

Luthor blasts J’onzz unconscious and throws him down, allowing Superman to tackle him from behind, damaging the suit and destroying it’s power source. Luthor mocks him, telling Superman to kill him, but Superman refuses, picking up Luthor and returning him to custody as J’onzz deactivates the reactor. 

Furious, Brainiac appears, using a portable bodysuit that attaches his mind to his ship. With enhanced strength, he fights both J’onzz and Superman, before Supergirl arrives and tackles him, dragging him out of the city and into the Metropolis Harbour. 

Though Supergirl fights well, partly damaging Brainiac’s suit and causing his computer-like mind to malfunction, she is overpowered as Brainiac breaks her hand. Superman and J’onzz both fight Brainiac, causing him to drop the Mother Box. When Brainiac knocks down J’onzz and strangles Superman, Kara opens a boom tube which transports Brainiac away from Earth. 

Kara reveals that she reprogrammed the Mother Box to send Brainiac to an unknown place, claiming it will take years for him to get back. They return to the city, where both J’onzz and Kara are cheered by the crowds. 

A month passes, and J’onzz, who has been dubbed by the media as “Martian Manhunter”, is offered by Bruce Wayne to join the Justice League. J’onzz accepts, telling Bruce and Diana that there are other threats they must look out for. 

Meanwhile, Luthor is visited by Waller in prison, where he suggests that Superman face Waller’s “new and improved” metahumans. Waller releases Manchester Black from Belle Reve, and he wreaks havoc on the city. He is confronted by both Superman and Supergirl, and as they charge to fight, the film ends. 

In a post-credits scene, Brainiac is transported into deep space, arriving on a strange planet. He sees a grey figure dressed in blue armour (Jeff Bridges) looking over him, who says “welcome to Apokolips, Brainiac.”