"Where are we?" Martha asked, turning in a circle to get the full view of the place. Streets of regularly-shaped houses, a creek bubbling in its bed. Trees with fresh green leaves, small flowers budding all around, both in freshly mulched lawns. She breathed in deep and sighed. "Mm, it smells like spring."
"An accurate conclusion, Dr. Jones, as it is spring," the Doctor said, stepping out of the TARDIS. "I'm afraid this one isn't all that interesting - just planet Earth, a few years into the future. I was aiming for the planet Splee a couple thousand years from now, but I suppose the TARDIS didn't want to go to Splee." He glanced back at his ship. "Mind you, there was an unfortunate incident the last time we were on Splee. The TARDIS ended up covered in pink slime."
Martha eyed the Doctor, frowning. "Pink slime?"
"Oh, nothing to worry about!" he said. "That happened a good two hundred years after the date I wanted to go to, you'd be fine. Still," he shrugged. "Since we're here, do you want to...?"
Martha looked around and smiled. "Sure!" Following the Doctor down one of the streets, she said, "It'll be nice to see where the world's going." Looking slyly at the Doctor, she added, "Get a look at the stocks. Maybe when I go home, I can invest in - "
"Watch it," the Doctor said, turning a disapproving look her way. "None of your future knowledge is to be used for personal gain."
"I was only joking!" Martha protested, laughing. When the Doctor didn't join in, her laughter trailed off awkwardly. "Okay, maybe it wasn't that funny," she muttered, frowning. She caught sight of the Doctor's serious expression. "Doctor? What is it?"
Looking around slowly, the Doctor asked, "Does anything feel... funny to you?"
"Funny?" Martha looked around; they'd approached a schoolyard, where a few kids were running around, playing. She shrugged. "Looks alright to me."
"No," the Doctor breathed. "No, something's wrong here. What is it?" he wondered.
One of the children bent over, sneezing, and a teacher rushed over, a hand to the child's forehead.
"Look at that," the Doctor said.
"That's pretty fast action," Martha said approvingly. "Good. Kids can spread germs like nobody's business. Best to get them to the nurse's ASAP." When the Doctor didn't respond, she asked, hesitantly, "Right?"
The Doctor shook his head. "No, no, it's a bit too fast. Like they were expecting it. And where are all the other children?" He gestured at the small group of children and the large school behind it. "A school this size, there should be twice as many children out at playtime as this, easily! No, something's wrong."
Susan Polinski, the school secretary looked up from her computer to see a man in a trenchcoat and a black woman with a spiky-looking hairdo watching her expectantly. The man held out a wallet which, when opened, revealed a very official looking badge.
"Hello," he said with a British accent, "Dr. John Smith, that's Dr. Martha Jones," nodding at his companion, "we're here on behalf of WHO."
"Oh my," Susan said, concern coloring her voice. "What's wrong?"
"We're looking into the recent widespread occurrence of quickly-spread illnesses," Dr. Jones explained. "Your school seems to have had it particularly bad - could we speak to the nurse?"
"I'm afraid not," Susan said apologetically. When the doctors frowned at her, she explained, "Out sick. We've been sending the kids to Mercy General, down town."
"What's she got?" Dr. Smith asked curiously.
"Same thing everyone's got," she said, surprised that the doctors didn't already know. But, by the looks on their faces, they didn't, so she told them.
"Swine flu," Martha repeated disbelievingly. "You sure she didn't mean avian flu?"
"Nope!" the Doctor declared. "H5-N1 is old hat these days; it's all about H1-N1." He marched up to the hospital, Martha hot on his heels.
"And 'these days' is...?" she prompted.
"2010!" he chirped. Then: "Wait, no. That's not right. That epidemic was in 2009."
"But, Doctor," Martha started, "you saw that school. There's too many kids out sick for this to not be an epidemic."
"That may be," the Doctor said slowly, considering, "but they've already got a vaccine for this flu. There's no reason that it's spread so far. Unless..."
"Unless it's not an ordinary flu," a man behind them said. Martha and the Doctor turned to look at him, shocked, which only increased when they saw him. He was wearing a dark suit under a trenchcoat, both of which were ragged and torn at the edges. His face was covered with bruises and scratches that made him look like he'd come out worse in a fight. And a closer look on Martha's part showed that he had dried blood stains on his undershirt, in a strange pattern.
"You alright?" she asked carefully.
"You're right," the man said to the Doctor, ignoring Martha. "But this isn't your battle. You should leave."
The man walked past the Doctor, further into the hospital. "Yes," he said over his shoulder, voice rough.
The Doctor followed, ran in front of the man and walked backwards to keep facing him. "But what do you mean, leave?" he asked again. "There are people hurt here, people who are sick, and if something unearthly is causing it it's my responsibility to - "
The man cut him off. "And when He had opened the fourth seal, I heard the voice of the fourth living being say, 'Come and see!' And I looked, and behold, a pale horse, and his name that sat on him was Death, and Hell followed with him. And power was given unto them over a fourth part of the earth to kill with sword, and with hunger, and with death, and with the beasts of the earth."
The Doctor's jaw dropped.
"In other versions of the text," the man added, "hunger is called famine, and death pestilence."
"But - but - " the Doctor stammered. "That's not possible."
"It is," the man insisted. "It's happening now, it's been happening for a year, and it's going to continue to happen if you don't let me past!" With that, he shoved past the Doctor and approached the Help Desk at the back of the room, asking something about the CDC.
"Doctor," Martha said quietly, "was that... Revelations? Did he mean what I think he meant?"
The Doctor glanced down at her. "What, that it's the Apocalypse and the world's going to end?"
She giggled a little hysterically. "Yeah."
"Yeah, I think he did," the Doctor said, rubbing a hand over his face. "Worse than that, though, is what he is."
Martha looked up at him quickly. "What, you mean he's not human?"
"No, he's not. I didn't even think they existed," he confessed. "I just thought they were stories you people made up. But, if the source material for the Devil exists, I guess they could too."
Martha looked the man over skeptically. "Why, what is he?"
The apparent angel turned away from the Help Desk, which did not look to have been very helpful. He took two steps, faltered, and collapsed.
The Doctor winced, hissing sympathetically. "Ooh, and a sick one at that. Come on, we can't let him stay here." Flashing his psychic paper at the nurses who approached the angel's body, the Doctor got to work.