“I couldn’t disagree,” she murmured. Though she immediately wanted to crawl back beneath the parachute and hide from embarrassment, it was worth it to see Thorne’s grin become a little less forced.

They packed up their camp, drank some water, and retied the towels around Cress’s ankles, all while the taunting morning dew steamed and disappeared around them. The temperature was already climbing. Before closing up their pack, Thorne shook out the sheets and made Cress wrap one around herself like a robe, then adjusted his own sheet to make a hooded cloak that came over his brow.

“Is your head covered?” he asked, brushing his foot along the ground until he found the metal bar he’d been using as a cane. Cress tried her best to mimic the way he’d covered himself before confirming that it was. “Good. Your skin is going to crisp up like bacon soon enough. This will help for a little while at least.”

She fidgeted with the cumbersome sheet while trying to guide Thorne up the slope they’d camped on. She was still exhausted and half numb from walking. Every limb throbbed.

They hadn’t traversed four dunes before Cress stumbled, landing on her knees. Thorne dug his heels into the ground for purchase. “Cress?”

“I’m fine,” she said, pulling herself up and rubbing the sand from her shins. “Just a little drained. I’m not used to all this exercise.”

Thorne’s hands were hanging in midair, like he’d meant to help pull her to her feet, but she noticed it too late. Slowly, they sank to his sides. “Can you keep going?”

“Yes. I just need to get into a rhythm again.” She hoped it was true and that her legs wouldn’t be loose cables all day long.

“We’ll walk until it gets too hot, then rest. We don’t want to exert ourselves too much, especially under full sun.”

Cress started down the dune again, counting their steps to bide the time.

Ten steps.

Twenty-five.

Fifty.

The sand grew hot, singeing the soles of her feet through the towels. The sun climbed.

Her imagination circled through her favorite fantasies, anything to keep herself distracted. She was a shipwrecked pirate from the second era. She was an athlete training for a cross-country journey. She was an android, who had no sense of exhaustion, who could march on and on and on.…

But the dreams became more and more fleeting, reality pushing them aside with pain and discomfort and thirst.

She began to hope that Thorne would let them stop and relax, but he didn’t. They trudged on. Thorne was right about the sheets, which kept the merciless sun from scorching her, and she became grateful for the dampness of her own sweat keeping her cool. She began counting again as sweat dripped down the backs of her knees, and though she felt awful for thinking it, part of her was glad Thorne couldn’t see her in this state.

Not that he was immune to the trials of the desert. His face was red, his hair messed from rubbing against his makeshift hood, and dirt streaked down his cheeks where there was a shadow of facial hair.

As it grew hotter, Thorne encouraged Cress to finish off the water they’d opened in the morning, which she drank with relish, only afterward realizing that Thorne hadn’t taken any for himself. She was still thirsty, but the day was stretching on in front of them and they had only one more bottle. Though Thorne had told her they shouldn’t ration it, she couldn’t bring herself to ask for more if he wasn’t drinking also.

She began to sing to herself to pass the time, humming all the pretty songs she could recall from her music collection on the satellite. She let the familiar melodies distract her. Walking became easier for a time.

“That one’s pretty.”

She paused, and it took a moment for her to realize Thorne was talking about the song she was singing, and it took another moment for her to remember which one it had been. “Thank you,” she said uncertainly. She’d never sang in front of anyone—never been complimented on it. “It’s a popular lullaby on Luna. I used to think that I’d been named for it, before I realized what a common name ‘Crescent’ is.” She sang through the first verse again. “Sweet crescent moon, up in the sky. You sing your song so sweetly after sunshine passes by.…”

When she glanced back at Thorne, he had a faint smile on his lips. “Your mom sang you a lot of lullabies?”

“Oh, no. They can tell you’re a shell right when you’re born, so I was only a few days when my parents gave me up to be killed. I don’t remember them at all.”

His smile disappeared, and after a long silence, he said, “You probably shouldn’t be singing, now that I think of it. You’ll lose moisture through your mouth.”

“Oh.” Pressing her lips tight together, Cress placed her fingertips against Thorne’s arm, the signal that had come to mean they were starting down a slope, and slogged on. Her skin had been scraped raw by the heat, despite the shelter of her makeshift robe, but she was propelled on by the thought that it was nearly midday. And while midday would bring about the highest temperatures yet, Thorne had also promised a respite from walking.

“All right,” Thorne finally said, as if the words were being dragged up from his throat. “That’s enough. Let’s rest until the temperature goes down again.”

Cress groaned with relief. She would have kept walking all day if he had asked it of her, but how glad she was that he hadn’t.

“Do you see any shade at all? Or someplace that looks like it might be shaded when the sun starts going down?”

Cress squinted across the dunes. Though there was some shade over the occasional hillock, at high noon it was almost nonexistent. Still, they were coming up on a big hill that would soon cast some shadows—it was the best they could do.

“This way,” she said, spurred on by the promise of rest.

But as they crested one more dune, her eye caught on something in the distance. She gasped, grabbing Thorne’s arm.

“What is it?”

She gaped at the glorious sight, struggling to find words to describe it. Blue and green, a stark contrast against the orange desert sand. “Water. And … and trees!”

“An oasis?”

“Yes! It must be!”

Relief spilled over her. She began to tremble with the promise of shade, water, rest.

“Come on—it isn’t far,” she said, plowing through the sand with renewed energy.

“Cress. Cress, wait! Reserve your energy.”

“But we’re almost there.”

“Cress!”

She barely heard him. Already she could imagine the cool water slipping down her throat. The breeze beneath a palm’s canopy. Maybe there would be food, some strange tropical Earthen food she’d never tasted, that would be juicy and crisp and refreshing …

But mostly she thought of collapsing into a nice patch of shade, cooled and protected from the sun, and sleeping until nighttime brought the return of cooler temperatures and endless stars.

Thorne trooped after her, having given up trying to make her stop, and soon she realized she was being cruel to make him go so fast. She slowed a little, but kept her eyes on the lake that shimmered at the base of a dune.

“Cress, are you sure?” he asked when he’d caught his breath.

“Of course I’m sure. It’s right there.”

“But … Cress.”

Her pace slowed. “What’s wrong? Are you hurt?”

He shook his head. “No, just … all right. All right, I can keep up. Let’s get to this oasis.”

She beamed and grabbed his free hand, leading him over the desert’s ripples and tides. Her fantasies took over, eclipsing her fatigue. The towels had nearly rubbed the soles of her feet raw and her calves were sunburned where her sheet didn’t protect them and her brain was swirling with thirst, but they were close. So close.

And yet, as she slipped along the powdery sand, it seemed that the oasis never came any closer. It always lingered at the horizon, as if the shimmering trees were receding with each step she took.