Disclaimer: "Doctor Who" is the property of the BBC; I'm merely borrowing…

Special thanks, as always, to SonicJules for encouragement, beta assistance, and help with the title.

It was bloody hot: sweltering, roasting, broiling, fires-of-hell hot. Donna was sure she'd never experienced heat like this before. The sun's blazing rays had baked the ground into hard clay, and the few hearty, brave plants that had struggled to cling to life had long since lost the battle. They lay withered, brown, and brittle against the grey, dusty earth.

Donna paused for a moment to glance back at the Doctor. If she'd had any doubts about the intensity of the heat, his appearance quelled them. He'd removed his jacket, button-down, and tie and wore only his trousers and a pale blue tee shirt. She'd never seen him shed more than his jacket before. Oh yes, it was bloody hot indeed.

He was hunched over the contraption he'd set up beside the tent, feeding in the small rocks that contained some critical element required by the TARDIS for continued temporal travel. This planet—this blasted, barren, boiling planet—was the only place he knew to find the ore. To top that off, the deposits were widely scattered, and the only way to locate them was to undertake a visual search, scanning the ground for the glittery, slightly translucent pebbles.

They'd walked for three hours before they found the first deposit. The little rocks were strangely and incongruously heavy; a handful weighed as much as a small boulder. The element, hidden deep inside each stone, was much lighter, so it made sense to extract it here rather than attempting to transport the ore back to the ship.

The Doctor had come prepared for once, surprising Donna. He'd given her a rucksack that she'd slung over her back, and he'd carried a large duffle bag. Once they found the ore deposit, he took her bag and his and removed camping equipment, water, a large supply of nutrition bars, and the extraction contraption. The bags were clearly dimensionally transcendent. He'd pitched a tent rather impressively then settled down with the weird device while Donna gathered up the pebbles, bringing them to him one at a time.

"Just a couple more," he called, noticing her gaze upon him.

"Right," she replied, although she doubted he could hear her. Her voice was raspy and unusually soft. She gave a weary wave then trudged across the arid ground.

Her clothing was drenched in sweat, and her hair was plastered to her head. The hat she'd donned kept the sunlight out of her eyes, but she could feel the brutal heat scorching its way through her cotton shirt and khaki trousers.

Donna reached for the water bottle hanging at her side. She took a swig only to find that it was empty. She shrugged. There was more water at the camp. She'd refill the bottle when she returned with the pebbles. And then she'd take a much-deserved break. She'd eat a couple of those protein bars and drink at least two bottles of water…

The thought made her grimace. Nausea roiled through her, and she realized that food was the last thing she wanted. Shade was all she desired now. Just a couple more pebbles to go, and then she could slink into the tent, away from the relentless sun and singed ground and heat that radiated up and all around her.

She stumbled ahead, her eyes flicking over the ground. There were no pebbles in sight. She sighed and wiped the hair from her eyes. Perhaps she should have been surprised to discover that her skin was dry now; the constant stream of sweat had ceased. Instead, she smiled languidly. Temperature must be going down, day must be cooling off…

She trudged along for some time, but she couldn't find any more pebbles. A part of her urged her to return to the camp, but a bigger, louder part prodded her to continue her search. The Doctor had entrusted this task to her, and dammit, she'd complete it.

Her feet moved over the hard earth, and after a while she stopped paying attention to where she was going. Her thoughts grew hazy, her limbs inexplicably heavy, and the sunlight seemed to darken into splotches of black that danced before her unfocused eyes.

Her stomach was cramping now, and once she thought she would vomit, but she didn't. She coughed and retched a bit, but there was nothing to expel. She almost fell to her knees; however, sheer force of will, or perhaps it was just plain old stubbornness, kept her going.

"Donna!"

The voice was faint and very far away. Yet when she finally found the energy to look up, she found the Doctor standing just a few yards away. She was vaguely aware that she was near the camp. How had she gotten here? She curled her fingers into her palms. Damn. She hadn't found any more pebbles.

"Sorry," she croaked.

He was walking toward her, and though his legs seemed to move fast, his body approached her in slow motion. He was saying something, probably chastising her for failing to find any more ore, but she couldn't comprehend his words. She blinked as he wavered before her. The black spots were returning, darting around him, nearer and nearer, until they devoured him completely, and Donna saw nothing more.

To be continued...