- They will migrate all the people so that they can avoid the radioactive pollution
- There will be a new people who prevent the migration from happening. Possibly a race of deformed people. Emori and Murphy will be instrumental in diplomacy.
- War between Grounders and Arkaddians will be resolved.
- Octavia will get involved with the Ice King Roan
- There will be a faction of Grounders and Arkadians who won't want to leave and will try to stop the meltdowns. This will be a a mistake and a distraction costing lives. They will try and find a bunker to hide in. Possibly Mount Weather?
- Going back to space may also be an option
- There will be a radioactive cloud that kills some and reminds everyone of how little time there is.
- A new Commander will be chosen. There will be conflict between factions putting forward their candidate. Luna being a legitimate claimant will be challenged by the King of the Ice Nation. Indra may also stand.
- There will be other Nightbloods
- The Flame will be installed on the part of the Ark still in space and Lexa will watch over Earth as a guardian angel
- The Flame will be able to use the chips to provide telepathy between people.
- Jaha will continue seeking the City of Light and try to bring back ALIE
- There will be a love triangle between Clarke, Lexa, and Bellamy. That Clarke will hop between the City of Light and Earth
- Raven will use her technical skills to control the reactors
- There still isn't peace between the Grounders and the Arkadians. This will be addressed