- Guardians of the Galaxy
- Mister Fantastic / Reed Richards
- Invisible Woman / Susan Storm
- S.H.I.E.L.D. Academy
- Franklin Richards Storm
- Firestar / Ann-Gell
- Brawn / Amadeus Cho (first appearance)
- Doctor Doom
- Kree Empire
- Ronan the Accuser
- Norman Osborn
- The Goblin
- Norman Osborn
- Tiberius Stone (first appearance)
- Meredith Quill
- Bonnie Quill
- Ellie Gillan
- Dinah Gillan
- Clayton Quill (flashback only)
Scientists and engineers of Oscorp and Alchemax are launching "Sentinel 6", a upgraded version of the Sentinel 5 satellite into space. Norman Osborn and Alchemax CEO Tiberius Stone make their public speech about the satellite, declaring that in a few weeks, it will be made as the world's newest communication center. Through one of the Oscorp drones, however, Osborn and Stone are also being observed and overheard by Doctor Doom, who is still seeking Oscorp's technology for his plans to bring America to his knees. Also, learning of Osborn's announcement of the satellite is Ronan the Accuser, who views the satellite as the "perfect weapon" for his future plans in favor of the Kree Empire.
Meanwhile, Nathan Quill and Zoe Gillan are with Reed Richards / Mister Fantastic and Susan Storm / Invisible Woman testing their new Star Beetles, advanced drones which can travel anywhere (even outside Earth's atmosphere) in their territory while also watching Osborn's announcement of Sentinel 6, which they are certain to be a greater threat to Earth than the Slayers could be. Yondu Udonta and Rocket Raccoon are golfing with Drax the Destroyer serving as their caddy, while Nebula and Groot are at S.H.I.E.L.D. Academy training Franklin Richards Storm, Ann-Gell / Firestar and Amadeus Cho / Brawn. Two of the Star Beetles observe Doctor Doom, who voices his plans to take over Sentinel 6 and use its resources to gain access to the World's database, and Ronan the Accuser, who plans to convert the satellite into a Kree doomsday device to destroy Earth. Overhearing this, Nathan and Zoe (suiting up as Star-Lord and Gamora) assemble the rest of the Guardians of the Galaxy and (followed by Mister Fantastic and Invisible Woman) travel towards Sentinel 6, where they plan to set an ambush for both tyrants, while Firestar and Brawn look after Franklin. Arriving discreetly in the satellite, the heroes witness Kree Sentries breaking through the satellite and fight them off. One of the Sentries hacks Oscorp's robots and converts them into Kree Sentries, much to Osborn's dismay, and the Goblin's amusement.
The Goblin sadistically enjoys watching the chaotic event while mocking Osborn over what he created. The Oscorp-made Sentries begin wreaking havoc in the facility, and with Firestar and Brawn working to prevent them from getting out. Taking advantage of the issuing chaos, Doctor Doom also flies towards Sentinel 6, planning to upload the codex to the World's database into his armor. Once he arrives, however, Doom is attacked by Ronan, and the two fight over the satellite's control. Noticing the two tyrants in the satellite, Star-Lord and Mister Fantastic head into the core of Sentinel 6's control panels and disconnect it from the World's database, leaving the satellite connected only to Oscorp and Alchemax. Gamora and Invisible Woman also hack a database of Oscorp, discovering that Osborn (actually the Goblin in his mind) had also implanted a nuclear weapon system, which will end up annihilating not only the target threats, but anything in the satellite's main, even Earth. Overhearing this, the heroes decide that, to stop both Doom and Ronan, they must "perform the Ultimatum": to destroy the satellite.
Rocket hacks the satellite's rocket engines and steers the satellite as far away from Earth as possible. One of the Kree Sentries breaks out of Oscorp's facility and aims to reach a NASA outpost until Franklin stands in its way and destroys it before it can destroy the nearby F.E.A.S.T. facility, and Firestar and Brawn destroy the remaining robots. Doom and Ronan soon realize what is happening and begin attacking the heroes, while others battle Doom, Star-Lord takes on Ronan. After a fierce fight which takes place in the satellite's reactor room, Star-Lord defeats Ronan and tricks him into damaging the reactor. Star-Lord and the rest of the heroes are likewise are to defeat Doom, after which Groot teleports him to North Ice, Greenland, via Bifrost. They then escape the satellite before it explodes, causing the rampaging Kree Sentries to be self-destructed. Ronan survives the explosion and is teleported back to Hala, as he vows revenge on the Guardians. As the heroes are hailed for saving the day again, Osborn is dismayed to hear that the authorities have cancelled the creation of the next Sentinel satellite units for the safety of Earth. Worse for him, Goblin continues sadistically tormenting Osborn in his mind. Later at night, the Guardians are enjoying themselves at the Gillan farm, where Richards and Susan are having a good moment with their son Franklin, and Nathan is with his sister Bonnie watching the stars, reminding himself of his own moment with his father Clayton.
- Scott Menville as Star-Lord / Nathan Quill
- Laura Bailey as Gamora / Zoe Gillan
- Troy Baker as Rocket Raccoon / Sebastian Allan
- Travis Willingham as Groot
- Erica Lindbeck as Nebula
- William Salyers as Yondu Udonta
- Sofia Carson as Firestar / Ann-Gell
- Alan Tudyk as Mister Fantastic / Reed Richards
- Catherine Taber as Invisible Woman / Susan Storm
- Grey DeLisle as Franklin Richards Storm, Young Nathan Quill
- Eric Bauza as Brawn / Amadeus Cho
- Misty Lee as Meredith Quill
- Katie Leigh as Bonnie Quill
- Gwendoline Yeo as Ellie Gillan
- Tara Strong as Dinah Gillan
- Maurice LaMarche as Doctor Doom / Victor Von Doom
- Jonathan Adams as Ronan the Accuser
- Jeffrey Combs as Norman Osborn, the Goblin
- Liam O'Brien as Tiberius Stone
- The episode is entitled after the 1969 song "Space Oddity" by David Bowie.
- This is episode in the Guardians of the Galaxy's arc to feature more than one licensed song in the background.
- "Real Wild Child" by Iggy Pop
- "Wild World" by Mr. Big