“Well, in that sense we’re really all subject to the collective dictates of the swarm,” Katherine said. “Parambulator is what decides where we go when.”

“It truly is one of the most insidious instruments of social control ever devised,” Julia said.

Katherine looked mildly aghast. “But without it, we have a disaster.”

“That is what makes it so insidious,” Julia said. “One can always justify it by making the safety argument. We will all be slaves of Parambulator until and unless someone decides that some things are more important.”

Jianyu was looking alert and curious. “If someone did decide that,” he said, “it would change nothing unless the arklet in question was switched over to manual control.”

“It’s my understanding that this can be done at any time,” Julia said. “Was I misinformed?”

“No,” Jianyu answered, “but it would show up very prominently on Parambulator. It would set off alarms all over the Situational Awareness Network.”

“In that case,” Julia said, “we shall have to deal with the SAN when and if the time comes to take decisive action.”

IVY’S GRANDMOTHER, A GUANGZHOU-BORN, HONG KONG–RAISED woman who spoke only a few words of English, had ruled the family from a mother-in-law apartment over a garage in Reseda. Enthroned on a duct-taped La-Z-Boy and swaddled in crocheted afghans, she had handed down a series of diktats, pronunciamentos, and fatwas that had taken on the force of law within her family of three dozen direct descendants and in-laws scattered across the San Fernando Valley. While not indifferent to money, love, security, and other common psychological drives, she seemed to have been motivated by another need that was obscure and hence mysterious to most of those who paid fealty to her. Anglos might have Orientalized this as “face” or Confucian respect for one’s elders. Ivy came to understand it as a simple need for attention. Anyone who entered or left the house had to check in with Grandmother. And it was not enough just to poke one’s head in the door and say hello or goodbye; one had to sit down in the rattan side chair next to the La-Z-Boy and spend a few minutes and say a few words. Grandmother had no power to enforce this regulation other than finding arcane and baroque ways to wreak long-term revenge on those who flouted it.

Julia Bliss Flaherty, as Ivy now realized, was of the same stripe. Pinned down and obliged to justify herself, she would explain her actions in terms of some altruistic plan. And she might even believe it. But it wasn’t that at all. She was like Ivy’s grandmother. If you paid fealty to her, she would favor you, and your reputation and power would grow among all the others who did likewise. If you sent her off to an arklet and ignored her, you became an enemy of her and of her network. She wielded no power other than that. But, ignored long enough, she could become a mighty foe. Her status as an ex-president—and not just any old ex-president, but the one who had overseen the construction of the Cloud Ark and even used nuclear weapons to protect it—gave her credibility among the Arkies. It had become common to think of those as scattered and demoralized, just waiting for a leader to bring them identity and purpose. Ivy had lost track of whether that was an accurate perception or a self-perpetuating myth spread by J.B.F. In any case, it had taken on the force of reality.

She was sitting across the table from Tekla, wondering whether it would be productive to explain all of these thoughts to her. Would this Russian heptathlete care about, or understand, Ivy’s dead Cantonese grandmother in Reseda?

Maybe. But Tekla came from a tradition in which details were hoarded and dispensed on a need-to-know basis. Presented with too much information, she became baffled, bored, and finally irritated. Toward those who talked too freely, she felt the same sort of contempt as a businessman might feel toward a spendthrift. She just wanted to know what her job was.

The same quality made it difficult to get inside Tekla’s head. But that was okay. In a big organization with a military-style chain of command, you didn’t have to be everyone’s friend and treasured colleague. Markus understood as much, which was why he had ended up running the place. More Ivy’s speed had been the boutique operation that had been Izzy at Zero. Markus would have been terrible at that.

“This thing with Julia is a distraction. Nothing more,” Ivy said. “Much more important things demand my focus. Making a big deal out of it will backfire—give her more power than she deserves. But we can’t ignore what she is doing.”

Tekla was nodding. Good.

“I want you to go and visit her heptad,” Ivy continued. “You will go there in your capacity as Markus’s security chief. Do you understand? It is an official visit. You will explain that there have been problems with the Situational Awareness Network that could have dangerous consequences unless they are fixed. Beyond that, I just want you to listen to her. Because I think that she will try to bring you over to her side. It’s what she does with everyone. You would be a prize catch.”

“If she does as you predict,” Tekla said, “what should be my response?”

It was a measure of Ivy’s naïveté that she didn’t even follow Tekla’s question at first. Then she understood that Tekla was suggesting she might pretend to become one of Julia’s followers. She was volunteering to become a mole in Julia’s network.

Tekla stolidly watched Ivy’s face as Ivy figured it out.

“I would suggest taking no immediate action,” Ivy said. Which, in truth, was Ivy being not so much cagey as timid.

“Of course,” Tekla said, “to show eagerness is poor tactics, it will only arouse her suspicion.”

Ivy said nothing. Tekla explained, “I know many people with such minds.” And you obviously don’t, honey.

“My suggestion is that you report to me in person first and then we will come to a decision.”

“We?”

“I. I will come to a decision.”

“It is good that we meet here. In the Banana,” Tekla said.

“You like it?”

Tekla looked nonplussed. “It is not that I like it. The Banana is more secure.”

“From bolides, you mean.”

Tekla shook her head. “From Grindstaff.” Then she stood up—carefully, so as not to fly up and bang her head on the ceiling—and departed, leaving Ivy alone with a head full of questions. Had she really just embarked on the project of setting up an internal espionage network within the Cloud Ark? How was she going to explain that to Markus? Would he be horrified, or impressed? In either case, how would she feel about his reaction? When the hell was Dinah going to get back so that they could discuss this kind of thing over distilled spirits?

And what had Tekla meant by that last comment, that the Banana was more secure from Grindstaff? It was old, pre-Zero, and so its connection to the SAN was retrofitted and kludgy. Tekla seemed to be suggesting that if Spencer could hack the SAN to the extent of disconnecting Julia’s arklets from it, then maybe he could also hack it to the extent of placing other parts of the Cloud Ark—including the Farm, the Tank, and Markus’s office—under surveillance.

I know many people with such minds, Tekla had said. She was talking about Russian military and intelligence types, accustomed to the byzantine thoughtways of those professions. Perhaps Tekla herself had once been groomed as an intelligence asset. If Tekla really did become a mole in Julia’s network, then how could Ivy be sure that she was a straight-up mole, loyal to Ivy, and not a double agent, loyal to Julia?

THE SCRAPE WITH THE ATMOSPHERE HAD LEFT YMIR TUMBLING slowly as it hurtled away from the Earth on its new orbit. Calculating exactly what that orbit was took them fifteen or twenty minutes, and told them that they had fewer than four hours in which to take actions needed to save their lives.