Monsters vs Aliens ending explained (spoilers)

[carl]

Galaxhar(Rainn Wilson) captures Susan(Reese Witherspoon) and drains the Quantonium from her, making her small again. The Missing Link(Will Arnett), B.O.B.(Seth Rogen), and Dr. Cockroach(Hugh Laurie) get into the ship and free Susan. They manage to hack into the spaceship's computer and set the ship for self-destruct. This causes the ship to lockdown, seperating Susan from the other monsters. She breaks into the control room and fights Galaxhar. Galaxhar tells Susan that he can't override the lockdown and can't free the monsters. Susan sees that Galaxhar has drained the Quantonium into a glass ball and knocks it loose so that it lands right on her. Susan becomes giant again and saves the monsters. They escape the ship before it blows up, courtesy of Insectosaurus, who has sprouted wings, like a butterfly. General W.R. Monger(Kiefer Sutherland) tells the monsters that there is a monster terrorizing Paris. They all get on Insectosaurus' back and fly off....

[Brucemease]

It is revealed that the Company - specifically, Burke - sent the colonists on LV-426 to the Alien ship in hopes of obtaining an Alien for research purposes. Burke releases two facehuggers to impregnate Ripley and Newt, but the Marines intervene; Burke is exposed and nearly killed for his actions. However, at that exact moment, the Aliens attack in force, leading to the deaths of everybody except Ripley, Hicks, Newt, and the artificial person Bishop. While trying to escape, the Aliens capture Newt and injure Hicks; Ripley, loaded with weapons from the second dropship, enters the Aliens lair and confronts the Queen Alien to save Newt. Ripley frees Newt, decimates the lair, and returns to the dropship, with the Queen hot on her trail. As the dropship departs, the colonys fusion reactor overloads, destroying the colony (and the Aliens lair). Back aboard the Sulaco, all seems well until the Queen emerges from the landing gear area of the dropship. The Queen Alien tears Bishop in half and then chases Newt around while Ripley gets into a loader (seen earlier in the movie) and uses it to fight the Queen. Finally, Ripley manages to eject the Queen into space, while Bishop prevents Newt from being sucked out with the Queen. Hicks, Ripley, Newt, and the remaining half of Bishop finish by entering stasis for the trip back to Earth.

[frederick]

Selby realizes that Aileens murder spree is going out of control. She makes a tough decision to cooperate with the police in getting Aileen arrested. She testifies in court against Aileen and Aileen is sentenced to death. Aileen and Selby never spoke again.