When Does Osiris Reborn Take Place? Timeline & Canon

Where it sits in the Expanse timeline

Owlcat has given the same answer in three separate interviews. Creative Director Mishulin told GameRant the game runs “from the beginning of the first book to the end of the second book. Or if we’re talking about the show, from Season One to Season Two and a half.” He told Wccftech the same thing, and IGN’s announcement coverage uses the same phrasing.

One hands-on preview says “during the first season”. That is a journalist’s shorthand, and the developer quotes above outrank it. A Steam forum claim that the game is based on Caliban’s War and Babylon’s Ashes (book 6) has no official support at all.

Where the story starts

You play a mercenary with Pinkwater Security on shore leave on Eros when the station is locked down. The official store text and the announcement both frame the story around “those behind the Eros incident”. The Canterbury is already gone: the official Origins dev blog describes Mars being blamed for destroying it and Ceres left without water. Mishulin says you will feel “the repercussions of the destruction of the Canterbury and the events on Eros” and see some events “with your own eyes”.

The second mission, which is the one in the paid Beta, takes place on Pinkwater 4 station. Protogen mercenaries follow you there, and it is where you earn the title of captain. Some sites call it “Pinwheel”; the official name is Pinkwater 4.

Alongside Holden, not instead of him

This is not a retelling of the show. Game Design Director Rastorguev, speaking in September 2026: “Obviously Holden and his crew are a major part of The Expanse universe, but we have our own enemies.” Owlcat told CNET the story happens “at the same time, but not largely overlapping with” the show. In the Beta, a news report covers the Canterbury and Holden’s broadcast is mentioned without being shown.

Your antagonist is Protogen, the corporation behind the protomolecule. Previews of the Ganymede section describe protomolecule hybrids as enemies ⚠ previews only, no dev blog yet. Owlcat has not explained what “Osiris” in the title refers to. PC Gamer reads it as the name of a Protogen project, but that is the writer’s interpretation.

Locations

The store page and press release name Ganymede, Ceres, Mars and Luna, and the official site adds bunker complexes in the Asteroid Belt. At Gamescom 2025 Rastorguev listed Earth and Io as well ⚠ one interview. Your origin gates some of them early on: only Martians can land on Mars, Earthers have contacts on Luna, and Belters are welcome on Ceres.

Is it canon?

It is officially licensed. Owlcat develops and publishes it in partnership with Alcon Interactive Group, which holds The Expanse TV rights. The press release calls it “an original story” that “significantly expands the world of The Expanse depicted in the TV show and novels”. Owlcat says Alcon is “quite satisfied” with the work.

Two things are not established as of September 23, 2026. Nobody official has used the word “canon”. And James S.A. Corey, the pen name of novelists Daniel Abraham and Ty Franck, has not been announced as writing or approving it. The accurate wording is: licensed, same continuity, running alongside books 1 and 2.

Will show characters appear?

Yes, some. The press release says players “will encounter familiar faces from the TV show, as some actors return to their iconic roles”, and Rastorguev says some are digitally scanned and voiced by their original actors. None have been named yet. Owlcat has said it is too early to talk about who.

That includes Detective Miller. The Miller’s Pack pre-order tier (see editions) contains his OPA heavy armor, his revolver and a UN Spec Ops rifle. That is cosmetic gear, not a confirmed appearance. Your own crew are all original characters: see companions.

Do you need to watch the show first?

No. You play a new, customizable character, the villains are Owlcat’s own, and previews consistently call it newcomer-friendly. Owlcat hasn’t said “no homework needed” in those words, so that part is our reading. If you want context, seasons 1 and 2 of the show cover Eros, the Canterbury and Protogen, which are the three things the game assumes you have heard of.

Not the same as the Telltale game, or Exodus

The Expanse: A Telltale Series (2023) is a separate episodic game set before season 1, starring Camina Drummer. It is also licensed through Alcon, but no story link to Osiris Reborn has been announced. Exodus, which autocomplete pairs with Osiris Reborn, is an unrelated original sci-fi RPG from Archetype Entertainment. The two get compared because both are 2027 third-person RPGs in the Mass Effect mold (see the FAQ).

Open questions we’re tracking

• Which show characters and actors appear. Not named yet.
• Whether Miller appears in the story. Only his gear is confirmed.
• Whether the authors are involved. Not announced.
• What “Osiris” refers to. Not explained.

Frequently Asked Questions