Bellamy squeezed her hand. “As soon as we get Octavia back, we’ll go check it out.”

“Thank you,” she said quietly. “For everything. I know you lost a lot of time bringing me back here.”

“Yeah, well, it would have been a shame to lose the only doctor on Earth, even if you were arrested before you finished training. Can you remind me again which body part I should avoid injuring?” he said with a smile. “Are you better with elbows or ankles?”

Clarke was glad to see him in a playful mood, but it wasn’t enough to shake the guilt building up in her chest. She lowered her voice, glancing again at the girl across the infirmary. “It’s just… if you need to leave again, you should go. I feel terrible that you already lost a day because of me.”

His teasing smile softened. “It’s okay.” He reached up and absentmindedly began twisting a strand of her hair around his finger. “I think for now, my best chance is to see what this girl knows, before I go back looking for the trail.”

Clarke nodded, relieved that Bellamy didn’t resent her, and relieved that he wasn’t planning on leaving right away. “Octavia’s lucky to have you,” she said, then cocked her head to the side and surveyed Bellamy with a smile. “You know, I remember when I heard there were siblings on Walden.”

Bellamy raised an eyebrow. “My reputation precedes me? I guess I shouldn’t be surprised. How could you not talk about someone this good-looking?”

Clarke knocked against him, digging her elbow into his ribs. He made an exaggerated grimace, then laughed. “It’s true,” she continued. “My friend Lilly remembered you guys from the care center. I think her exact words were, ‘There’s a girl with an older brother. It’s great that she has a sibling, but he’s so spectacularly attractive, no one can look directly at him. It’s just too blinding, like staring at the sun.’ ”

Instead of smiling, Bellamy’s face went pale. “Lilly? It wasn’t Lilly Marsh, was it?”

Clarke’s chest tightened as she realized what she’d just let slip. Of course Bellamy and Lilly had known each other. There couldn’t have been that many children in the Walden care center, could there? Lilly had rarely volunteered information about her life on Walden, and Clarke hadn’t asked. It hadn’t been a conscious decision, but she realized now that it was easier to think about Lilly as a girl without a past, without people who cared about her.

“How did you know Lilly?” Bellamy was staring at her, searching her eyes for the information she was desperately trying to hide.

“I met her at the hospital, during my apprenticeship,” Clarke said, not bothering to count the number of lies in the short sentence. “Were you friends?” She prayed he’d shrug and say something about knowing her vaguely from the care center.

“We were—” Bellamy paused. “We were more than friends. Lilly was the only girl I ever cared about. Until you.”

“What?” Clarke stared at him in shock. Lilly, her friend and her parents’ test subject, had been Bellamy’s—

“Are you okay?” Bellamy asked. “Does it bother you that I had a girlfriend back on the ship?”

“No. Of course not,” she said. “I’m fine. Just tired.” Her heart racing, Clarke rolled onto her side before she could see the look on Bellamy’s face. Better he think she was irrationally jealous and possessive than do anything to hint at the truth.

“Okay,” he said, clearly unconvinced. “Because it was a long time ago.”

She didn’t turn around. Lilly’s death may have felt like a long time to Bellamy, but Clarke relived her friend’s final moments every day. She still saw Lilly’s face whenever she closed her eyes and tried to go to sleep. She still heard her voice echoing in her head.

Lilly’s death was never far from her thoughts. Because Clarke had been the one who killed her.

CHAPTER 7

Glass

Glass and Luke were silent as they left his flat for the very last time. As they stepped into the eerily empty corridor, Glass reached for Luke’s hand, shocked by the silence. The chaos that had overwhelmed the ship for the past few days seemed to have died down, washed away by a heavy tide of despair. The dim ceiling lights flickered wearily, like an exhausted child trying to keep his eyes open.

They took the main stairs quietly, finally reaching the lower levels of the ship, which were used to house the electrical and plumbing systems. Neither spoke until Glass pulled Luke to a stop in front of the air vent, then reached up to remove the grate.

“Please,” Luke said. “Allow me.” He pulled the grate from the wall and placed it on the ground with exaggerated delicacy. “And to think, all those hours I spent worrying what kind of date to take you on, it turns out we could’ve gone on a romantic crawl through the ventilation system.”

“It’s all your influence,” Glass said, managing a smile despite the prickle of tears she could feel building behind her eyes.

“What?” Luke reached out and ruffled her hair. “Slumming it?”

Glass rose up onto her toes to give him a kiss. “Being adventurous.”

Luke pulled her into a hug. “I love you,” he murmured into her ear. Then he boosted her into the vent, waited for her to climb inside, and replaced the grate.

Glass paused for a moment to wipe away the tears threatening to obscure her vision. “I love you too,” she whispered, knowing that Luke wouldn’t be able to hear it. Then she gritted her teeth and began to crawl down the narrow metal chute.

As she slowly made her way forward, straining to see in the dim light, Glass tried to imagine the look on her mother’s face when she opened the door. Would she be overwhelmed with relief? Or would part of her still be furious that Glass had risked her life by sneaking onto Walden? The thought of all the pain she’d caused her mother over the past year made Glass’s heart cramp. If this was the end, then she needed one last chance to apologize, one final opportunity to tell her how much she loved her.

Glass winced as her ankle knocked against the metal wall. If someone had told her two years ago that she would someday crawl through an air vent from Walden to Phoenix, she’d have laughed in their face. Things had been different then—she had been different. She smiled in the darkness. Now her life might be in danger, but it was finally one worth fighting for.

“… when the Cataclysm struck, there were one hundred and ninety-five sovereign nations, although the vast majority had joined one of the four major alliances.”

Glass yawned, covering her mouth halfheartedly. Their tutor had dimmed the lights to make the holograms easier to see, so there was little chance that she would notice that Glass wasn’t paying attention.

“In the first six weeks of World War Three, nearly two million people were killed…”

“Cora,” Glass whispered, leaning over the desk. “Cora.”

Cora lifted her head and blinked sleepily at Glass. “What?”

“… and in the next six months, more than five million died of starvation.”

“Did you get my messages?”

Cora rubbed her eyes, then blinked again, activating her cornea slip. She squinted as she scrolled through her unread messages, including one from Glass asking if she wanted to go to the Exchange after tutorial.

A few seconds later, there was a flash in the top right corner of Glass’s vision field. She blinked as a message from Cora appeared. Sure, if we’re fast. I have to meet my mother at 3.

Why? Glass blinked back.

Greenhouse duty

Glass smiled. “Greenhouse duty” was Cora’s family’s code for when they took an extra visit to the solar fields. It was totally illegal, but the guards turned a blind eye because Cora’s father was the Resources Chief and no one wanted to risk upsetting him. Glass didn’t really care that Cora’s family got the best produce this way—her family had perks of their own—and Cora let her come over for fresh berries every now and then.

“Yes, Clarke?” The tutor gestured toward a girl in the front row who had her hand raised. Glass and Cora rolled their eyes. Clarke always had a question, and the tutors were so delighted by her “intellectual curiosity” that they let her babble on, even after class was supposed to have ended.