Five years after Kyra's death, Riddick has become increasingly uneasy in his role as Lord Marshall of the Necromonger fleet. His refusal to swear into the Necromonger faith has caused dissent among his subjects and assassination attempts by his subordinate commanders. Riddick strikes a deal with Commander Vaako: the location of Furya and a ship to take him there, in exchange for Vaako becoming the next Lord Marshall, so that he can achieve what he calls transcendence. Led by Vaako's aide, Krone, Riddick and a group of Necromongers arrive on a desolate planet. Recognizing that it is not Furya, Riddick kills most of his escort when they attempt to assassinate him. In the chaos, Krone causes a landslide and buries Riddick alive.
Eons ago, Bor, father of Odin, clashes with the Dark Elf Malekith, who seeks to destroy the universe using a weapon known as the Aether. After conquering Malekith's forces, including enhanced warriors called the Kursed, on their home world of Svartalfheim, Bor safeguards the Aether within a stone column. Unbeknownst to Bor, Malekith, his lieutenant Algrim, and a handful of Dark Elves escape into suspended animation.
On an asteroid, the Terran Federation's Fort Casey is crawling with bugs. The starship Alesia begins to deploy its Mobile Infantry troopers, by dropship, to seize and control the hangar and rescue any survivors. Lieutenant Daugherty's 'Alpha' team lands and immediately engages bugs, fighting through to rendezvous with the surviving Fort Casey troopers. After setting explosives charges, the troopers head to the starship John A. Warden for evacuation, only to see it leave dock without them – Minister Carl Jenkins has commandeered the Warden from Captain Carmen Ibanez, sending her to Alesia. Before leaving, Jenkins orders that Major Henry "Hero" Varro, the commander of Fort Casey's K-12 troopers, be escorted to Alesia as a prisoner. Alesia docks with Fort Casey for emergency evacuation of the surviving troopers, and the Fort Casey asteroid is successfully destroyed.
The film starts with Adam telling the story of his two-planet home world, unique from other planets or planetary systems as it is the only one that has "dual gravity". This phenomenon of dual gravity allows the two planets to orbit each other in what would otherwise be impossibly close proximity. There are three immutable laws of gravity for this two-planet system:
In 965 AD, Odin, king of Asgard, wages war against the Frost Giants of Jotunheim and their leader Laufey, to prevent them from conquering the nine realms, starting with Earth. The Asgardian warriors defeat the Frost Giants and seize the source of their power, the Casket of Ancient Winters.
Royce (Adrien Brody) awakens to find himself parachuting into an unfamiliar jungle. He meets several others who arrived in the same manner: Los Zetas drug cartel enforcer Cuchillo (Danny Trejo), Spetsnaz soldier Nikolai (Oleg Taktarov), Israel Defense Forces sniper Isabelle (Alice Braga), Revolutionary United Front officer Mombasa (Mahershala Ali), death row inmate Stans (Walton Goggins), Yakuza Inagawa-kai enforcer Hanzo (Louis Ozawa Changchien), and a general practice doctor Edwin (Topher Grace). An unnamed soldier dies when falling to the ground due to parachute failure.
By 2154, humans have depleted Earth's natural resources, leading to a severe energy crisis. The Resources Development Administration, RDA for short, mines for a valuable mineral – unobtanium – on Pandora, a densely forested habitable moon orbiting the gas giant Polyphemus in the Alpha Centauri star system. Pandora, whose atmosphere is poisonous to humans, is inhabited by the Na'vi, 10-foot tall (3.0 m), blue-skinned, sapient humanoids who live in harmony with nature and worship a mother goddess called Eywa.
On Planet 51, green humanoids with snail-like feelers and pointed ears live peacefully in a society reminiscent of 1950s America, but with alien technology and with 1950s-themed alien homes. In the town of Glipforg, Lem is a teenage boy with a new part-time job at the local planetarium and a long-time crush on his neighbor Neera. His best friend is Skiff, a big fan of the Humaniacs films. At a barbecue Neera's family is having, Lem tries to ask her on a date, but her hippie friend, Glar, keeps interrupting with his protest songs.
During the Clone Wars, Jedi Knights Anakin Skywalker and Obi-Wan Kenobi lead a small Republic clone army against the Separatist droid army on the planet Christophsis. Awaiting reinforcements, the two Jedi greet a shuttle carrying the young Jedi Ahsoka Tano, who insists that she has been assigned by Jedi Master Yoda to serve as Anakin's Padawan. Anakin begrudgingly accepts Ahsoka's apprenticeship, and the two succeed in deactivating the Separatists' energy field while Obi-Wan stalls the droid army commander, allowing a Republic victory.
In the past eleven years of "The Second Bug War", the Mobile Infantry has improved their weapons and tactics. However, as they adapt, so do the Bugs, and many new Arachnid variants have developed. The United Citizen Federation now finds itself engaged in trench warfare on the frontier planets. The Federation puts a positive spin on this in the media while using its judicial and military authority to suppress peace protesters and religious fanatics as seditionists.
During a space battle over Coruscant between the Galactic Republic and the Separatist Alliance, Jedi Knights Obi-Wan Kenobi and Anakin Skywalker lead a mission to rescue the kidnapped Supreme Chancellor Palpatine from Separatist commander General Grievous. After infiltrating Grievous' flagship, the Jedi engage Count Dooku in a lightsaber duel, which ends with Anakin killing Dooku at Palpatine's urging. Grievous flees the battle-torn cruiser, which the Jedi crash-land on Coruscant. There, Anakin reunites with his wife, Padmé Amidala, who reveals she is pregnant. Initially excited, Anakin begins to have premonitions of Padmé dying in childbirth.
After escaping the dark planet, Richard B. Riddick has been in hiding for five years, evading most of the bounty hunters and mercenaries that are set to capture him because of his high price on his head. His latest hideout is a Planet U.V., a world lit only by ultraviolet light.