The Word Lords track Seo and Dave down, and find them in the library. The two are restrained, but not killed. Apparently, Atrus' judgement has been accepted, and for that reason, the Word Lords won't kill them.

But the moment that Seo and Dave can return to their own home universe, they must.

"That's not why you're really sparing our lives, though," Seo accuses. "This is all to do with him. With Atrus! What's he to you?"

The Word Lords ignore her.

They turn to Atrus, and praise his oratory skills as being as incredible as his Art of writing Ages.

"Ages," Seo says. "It's interesting, this business of writing Ages. Isn't it?" She folds her arms. "Atrus was telling me about Riven. He said it was an ambitious world that should never have been written — interesting, considering that the Word Lords have written far more ambitious things on a regular basis."

Atrus is baffled that Seo remembers him telling her things that he didn't actually tell her — just wrote in his journal. As if his journal entry had been their conversation.

"You write the rise and fall of galaxies," Seo continues. "Planets. Pocket universes." With a pointed look at Atrus. "Civilizations."

There's a moment of unease in the room.

"But it's not just the really big things you write," Seo continues. "You can rewrite the nitty gritty small things, too. Even to the point of rewriting one single person's life… to make sure they cause certain events to happen. Make those great big civilizations fall." She steps forwards. "Thing is… I know why you're so obsessed with Atrus. I've figured it out."

Seo takes a book off the library shelves.

It is the Book of D'ni, and the chapter she has flipped to is one that's been rewritten and changed, the living language altered. Atrus looks inside the book.

The Word Lords rewrote Atrus' family.

So that his grandmother would destroy D'ni and end that civilization.

"They wanted to make sure you didn't bring it back," Seo explains to Atrus. "The civilization. Or the Art. They were planning to keep you here forever. Just to make sure you couldn't pass on your Art to anyone else."

Eager to change the subject, the Word Lords suddenly produce the Riven book for Atrus, telling him to take Seo and Dave and go inside to save Catherine.

"Riven is now stable," the Word Lords assure Atrus. "Our Laws of Language mean that we can't undo the damage that's been done to Riven already, but we have stopped that damage from going any further."

Atrus takes Riven.

But no longer trusts the Word Lords.

"Why did you destroy D'ni?" Atrus demanded. "Why did you rewrite my family, to make sure that D'ni fell?"

"The same reason the Time Lords wanted to restrict time travel," says Seo. "This lot things writing Ages is their skill. And they don't want anyone else doing it."

Atrus feels betrayed.

But knows he can't let this betrayal stop him from saving Catherine and evacuating everyone from Riven.

Atrus tells Seo and Dave his plan for Riven. Riven is an Age which his father, Ghen, rules, and Ghen is insane and very dangerous. If Ghen can link out of Riven, he'll wreak havoc — and Atrus can't allow that.

Therefore, Atrus will wait outside, while Seo and Dave link to Riven and find Catherine. He gives them both a 'trap book' that he's written — which looks like a normal linking book, but if you use it, you'll wind up trapped in a dark void with no way out.

Seo stops Dave before he can link through to Riven.

"There's no need to leave anyone behind," Seo tells them all. "Dave and I can't perceive your universe correctly without my ship's translation circuits, anyways. And nothing can break into Oliver. We'll just go to Riven using that!"

They head off to Oliver.

Seo redirects her ship so that it travels through the verbal portal that the living text of the Age has created.

…nagebsdrowehterehwgninnigebyrevehtotthgiryrotsehtpudnapudnapudepsevaD…

…and back and back…

On the way to Riven, while traveling in Oliver, Seo — suspicious of the Word Lords — flips through Atrus' trap book. She discovers that the Word Lords have torn out a page from the Trap Book, which means the Trap Book won't work.

But she doesn't tell anyone about this.

They land.

Seo gives Atrus the key to her ship and makes Dave surrender his own key. She locks her key and Dave's key up inside the ship, and turns back to Atrus.

"There's only one way back into this ship," she says, "and to the return linking book it contains. You have it." She folds his fingers over it. "Hide it somewhere that only you know. And don't tell anyone where. Not me. Not Dave. Not Catherine. Not even your journal."

They leave the ship.

As they're exploring Riven, Seo and Dave's relationship seems to be breaking down. She and Dave keep arguing, and getting into little fights.

Then Seo gets sucked through a plot hole, and winds up in the past of Riven.

…nagebsdrowehterehwgninnigebyrevehtotthgiryrotsehtpudnapudnapudepsevaD…

…and back and back…

Seo, since she got there, has been trying to work out why the Word Lords are so eager to get Atrus to Riven — and to make sure that Atrus didn't trap Ghen.

Clearly, the Word Lords want Ghen for something.

Question is, what?

The plot hole that Seo has fallen down turns out to be a plot hole that has to do with time. The amount of time between Catherine's showing up in Riven and Seo, Dave, and Atrus showing up in Riven seems to be rapidly fluctuating, changing on a regular basis.

An inconsistency in the plot!

These fluctuations are not caused by the Word Lords, they're caused by the decay of the universe. This gives Seo an advantage, because the Word Lords hadn't expected her to get sucked into Riven's past. Perhaps whatever the Word Lords want to hide from Atrus will be evident, here.

In this timezone in Riven, Catherine is still trying to work against Ghen, and hasn't been captured by him. Seo finds Catherine and speaks to her. From this discussion, and from the evidence that Seo saw in Riven's future, Seo gathers she understands what's supposed to happen to Catherine.

After speaking with Catherine, Seo is certain that whatever the Word Lords are up to, it doesn't just involve Ghen. It also involves Catherine.

Seo also doesn't exactly trust that the Word Lords have actually stabilized Riven.

Seo convinces Catherine to go off and face Ghen. When they do, Seo makes sure that Ghen doesn't harm Catherine by informing him that there's a time machine out there that's powerful beyond belief — and Atrus is the only one who knows where the key to that machine is located.

Catherine is needed alive, as a bargaining chip, for Atrus' cooperation.

As for Seo herself, she tells Ghen that she's there to save his life. But to do that, she first needs to figure out what, exactly, is going on, here.

…nagebsdrowehterehwgninnigebyrevehtotthgiryrotsehtpudnapudnapudepsevaD…

…and back and back…

The story shifts between the two separate times, one with Seo and Catherine and Ghen, and the other with Atrus and Dave wandering around Riven and working out all the puzzles.

Dave confesses to Atrus some of his love troubles — that he loves both his wife and Seo, and can't give up either. He also mentions that he and his wife have two sons, both children right now. Seo doesn't know that they exist, because Dave knows Seo would never continue the affair if there were children involved — she has no love for Alonna, but Seo won't hurt a child.

Atrus mentions that Dave should spend more time raising his sons, and less time with Seo. He tells the story of his own sons, as a cautionary tale.

…nagebsdrowehterehwgninnigebyrevehtotthgiryrotsehtpudnapudnapudepsevaD…

…and back and back…

Seo, in the past, establishes that Riven is still unstable, but in a different way. She figures out that its instability is such that it will condense into a singularity if a certain number of measures are met in a particular spot — the island where the Great Tree used to be, before Ghen cut it down. Wondering what's so important about that spot, Seo goes there with Catherine.

…nagebsdrowehterehwgninnigebyrevehtotthgiryrotsehtpudnapudnapudepsevaD…

…and back and back…

Back in the future, Dave and Atrus also make their way to that island.

And thus… the Word Lords' trap is set.

Seo realizes her mistake when she arrives. She suddenly gets very distinct clues that allow her to see that the Word Lords have already noticed the time discrepancy between herself and Atrus, and how the time between their two timezones keeps changing. The Word Lords have used this to their advantage.

Whether a remnant of the Great Tree, or due to the fact that both Atrus and Dave are on that island, as are Seo and Catherine and Ghen — the energies being channeled on that island are vast, and getting vaster and vaster by the second.

Vast enough to destroy Riven and cause chaos!

Seo realizes the only way to stop the chaos is to get out of the Riven book, and rewrite it from the outside. Seo manages to do that by purposely creating another plot hole — but one that revolves around the Word Lords.

When she jumps through it, she falls out of Riven and winds up back with the Word Lords.

She races over and opens the Riven book back up — just in time to see the Star Fissure energies make the two timezones collide on that island. Combined with the unbelievable force of the island itself and the Star Fissure, the Riven book implodes in a brilliant ball of white light.

Next thing Seo knows, the Riven book — along with Seo's ship, Dave, Catherine, Ghen, Atrus, and everyone else inside it — has transformed.

Into an unspeakably powerful energy source. That can temporarily stop the collapse of the universe.

Through Seo's connection with her ship, she feels a horrible pang. She feels everyone dying — and Oliver dying, with them.

Riven is gone.

All her friends are dead.

…nagebsdrowehterehwgninnigebyrevehtotthgiryrotsehtpudnapudnapudepsevaD…

…and back and back…