It took longer than normal for Stefan and the Doctor to abseil down into the cave.
Peter had lost his harness somewhere down under the water, meaning that Stefan had to first come down with his rucksack and shotgun and then make a second trip to retrieve Peter's equipment.
Once on the ground for a second time, he immediately sent the harness back up so that the Time Lord could follow after him.
Rushing to unclip himself, the Doctor bolted around the edge of the pool to Rose as quickly as his sneakers could carry him.
She gratefully accepted a warm hug off of him.
"Are you alright?" He whispered in her ear. "You're not hurt?"
"N-no. I'm g-good." She replied, struggling to speak. "Just cold."
"You're in the early stages of hypothermia," Peter told her. "Here, put this on."
Bending down to reach into his rucksack, he quickly produced a first aid emergency blanket. Unwrapping the silvery foil-like sheet, he came over and draped it around her shoulders. Instantly Rose felt warmer as the insulating material prevented her body heat from escaping.
"Thanks." She mumbled. "But what about you?"
"Keep it on until you dry off." He said, ignoring her. "But don't get too comfortable. That creature is still around here somewhere, I'll bet it won't be too far away."
Though this was true, Rose was more fascinated by the fact that Peter was still not shivering even in the slightest. Stood consulting with Stefan, the lieutenant was dripping wet and seemed to be in no rush at all to dry himself off.
An unusual reaction that the Doctor had also noticed.
"You should put one of those on too." He told him, watching the soldier carefully. "You don't want to catch a cold."
"It's water, I'll live," Peter grumbled back. "But thanks for the concern."
Lifting his rucksack, however, he visibly winced as he slung it onto his back. Using only the left strap to carry it, this was further evidence that he was in more pain than he was letting on.
"You okay, mate?" Stefan asked. "I told you it wouldn't be a nice landing."
"I'm fine." Peter insisted. "It's just a bit bruised from the impact, that's all."
"A fall from that height, I'm surprised you didn't break your collarbone." The Doctor pointed out. "Or dislocated your shoulder at the very least."
"Don't worry, Doctor," Stefan remarked. "He's done this kind of thing before. Besides, his head is plenty thick enough to land on."
"Thanks a bunch," Peter muttered good-naturedly. "Still, at least it wasn't my fault this time."
Rose suddenly felt embarrassed.
He was right. It was her fault, and he had warned her about getting too close to the hole.
"Sorry." She apologised. "I didn't mean to -"
"It's fine." He told her. "Could have happened to any of us, I suppose."
"Thank you, Lieutenant Argent." The Doctor said sincerely. "For going after Rose. Not many people would have been that quick to react, or brave enough to make the jump."
Sliding his rucksack on properly now, Peter shrugged the heroism off with ease.
"Well, looking after humans is part of my job." He said. "Also you can drop the formalities, Doctor. I don't like them much when I'm out in the field."
The Doctor smiled at the younger man.
"Peter it is then." He declared. "Nice to meet you."
The soldier said nothing back, but he was looking far less hostile than he had a moment ago and it was a step in the right direction at least.
Scanning the cavern with his torch, Stefan was still not having any luck in locating the creature or where it might have disappeared to. The floor space of the cave was almost entirely taken up by the pool of water, and the only entrance looked to be the hole above them.
"I don't get it, where could this thing have gone?" He questioned. "It can't have just vanished?"
"It made a grab for us when we dropped." Peter reminded him. "It could have…"
The lieutenant's nostrils flared as he stopped talking and breathed in a deep lungful of air.
Turning on the spot as though compelled to follow whatever it was he alone had detected, he focused his attention squarely on an isolated pocket of the cave opposite the pool of water from where they were stood.
Snatching the torch out of the Doctor's hand, he pointed the beam of light in the same direction. "I don't think the creature is going to be a problem anymore." He announced. "Over there. Do you see it?"
Rose's heart skipped a beat when she saw the huge black mass of leathery skin. However, she quickly realised that it wasn't moving from where it was lying halfway out of the water, its upper half sprawled out on the rocky ground.
The blood surrounding it glistened in the light.
It had splattered everywhere and was slowly seeping away from the crushed remnants of the alien's skull. Meandering slowly down to the water, the gory remains were beginning to turn the pool a grim shade of scarlet.
Seeing this, Stefan rounded on Peter with a stern frown on his face.
"Didn't I mention something about you breaking your neck?" He asked him rather pointedly.
"Well, technically it smashed its head in. The neck looks perfectly fine." Peter replied, shrugging. "Besides, you know that I'm tougher than those things."
"Stupider and luckier, perhaps."
Smiling at his friend, Peter brought his radio up to his lips again.
"Becker, listen up." He reported. "The creature is dead, but there's at least one more of them to deal with. You and Hart double back to base and report to Kensington. Tell him I want two guards posted at the entrance of the cave until the situation changes. The first watch can bring one of the jeeps up with them."
"What about you, boss?" Becker replied. "Are you going in to take a look?"
"Yeah, we'll see how far we can get. The primary and the creature have to be down here somewhere. Leave the rope in place so we can get back out."
Hearing this, the Doctor grinned at spotting an opportunity for him and Rose to stay.
Ensuring himself and Rose left with Becker and Hart would almost certainly delay the lieutenant from setting off on his mission, something which they both knew he couldn't afford to do.
"Does that mean…?" He ventured. "Both of us, mind you."
"Don't make me regret it," Peter told him. "I'm still in charge. You do as I say, got it?"
"Sir, yes sir." He said, giving a little mock salute. "Whatever you want."
Peter rolled his eyes but did not retaliate. Bringing his radio up again, he began to relay more orders to Becker and Hart.
"Okay, we'll rendezvous back here no later than sunrise. That's in…" He paused to consult his watch. "Eight hours."
"We'll lose radio signal," Stefan told him. "This cave could go way deep and we'll be on our own."
"We don't have a choice. The primary has to be found tonight or I don't think we'll find her at all."
"Okay," he agreed. "Four hours there, four hours back. Sounds like a plan."
"Becker," Peter added over the radio. "Listen, if we're not back by dawn. I want you to contact Major Harrison at Southampton. His team is on standby and are ready to back us up."
"Copy that, sir," Becker replied. "Good luck to you. Rendezvous in zero eight hundred hours."
The radio fell silent as the two remaining torches above them vanished from sight.
Clipping his radio back onto his belt, Peter then tossed the torch he'd been holding back over to the Doctor as he began to check over his equipment.
His gun, knife and baton were all still there, and once satisfied that neither had been damaged by the fall, he retrieved his shotgun from where Stefan had propped it up against a rock.
"Let's get this done." He announced. "You all set, Stefan?"
The corporal nodded back confidently.
"Ready when you are."
Rose could see how much the two men were enjoying themselves. No matter what dangers came with the job it was clear that they both revealed in the challenges of it.
"You like this, don't you?" She ventured. "Doing this job."
Peter had a grin on his face she hadn't seen before. It was that most relaxed she had seen him be all night.
"Getting to hunt down monsters whilst saving the world?" He replied. "Yeah, I guess it has its perks."
"At least you're modest about it." The Doctor pointed out. "Still, with you two fine soldiers and us on the job it shouldn't be too much of a task, should it?"
Peter's smile faltered as he saw the Doctor pull the sonic screwdriver out of his coat pocket.
"Put that thing away, Doctor." He ordered him. "It gave me a hell of a headache the last time you used it."
"It did rather, didn't it?" The Time Lord questioned. "I wonder why that was?"
Was he wrong or did a flicker of fear just cross the lieutenant's face?
Ignoring it for now, however, the Doctor did as he was instructed and pocketed the sonic screwdriver. Looking all-around at their surroundings, he began to search for a way they could venture further down into the caves.
"There's an opening this way. Come on."
Peter was pointing towards a slender passageway towards the far lefthand side of the cave. In the dank darkness, it was almost impossible to see without using a torch.
"Good spot." The Doctor admitted. "How did -"
"They're called eyes, Doctor," Peter replied as he strode past him. "You should try using them sometime."
Four hours of exploration seemed like an awfully long time for one cave.
But the longer and deeper they ventured made Rose feel more and more certain that they were going to run out of time. The creatures who had come to dwell in this underground world had greatly extended what was already a labyrinth of caverns and tunnels. Some were large enough to fit a house inside, whilst others were only able to fit one person in at a time.
No matter the size of each one, Peter and Stefan had made a point to search each of them meticulously.
This had slowed them down considerably, but the two soldiers knew they couldn't risk rushing their search and miss finding a clue that might lead them to their target.
After three hours of searching, however, there had been nothing to show for their efforts.
"This is getting ridiculous," Rose stated. "There's nothing down here."
"So far there isn't," Stefan told her. "There might be dozens of those things still waiting for us. There's one more for sure along with our missing woman."
"So we carry on."
"Until we find them both. Yes, we are."
Wiping her brow with the back of her hand, Rose grimaced as she felt the sweat lift off of her face and dribble down her skin. The air had become humid and muggy, enough to begin to make her feel drowsy and breathless.
Pausing to take off her denim jacket, she wrapped it around her waist over the top of her borrowed coat.
"Can we stop, just for five minutes?" She panted. "It's so hot down here."
Up at the front, Peter let out a frustrated sigh and consulted his watch.
He and Stefan had stripped down to their shirts and placed their protective vests back on over them. Both men were equally dripping with sweat, their faces and arms covered in a growing layer of grime and dirt from crawling into the smaller caves.
But they had not allowed the unpleasant conditions to slow down their relentless pace.
"We've been going for three hours." He replied, as though it were no time at all. "Sixty minutes before we need to turn around."
"That was before we knew how big this cave was." The Doctor pointed out. "If we turn back before finding this missing woman..."
"She's as good as dead." Peter agreed. "Fine, we'll stop for five minutes. No longer, understood?"
"Yes, sir." The Doctor replied, grinning. "Very good, sir."
He had barely spoken a word since they had begun their search, and it had mainly been Peter and Stefan consulting with one another on the possible route to take through the caves which had broken the otherwise silent march.
This was something the lieutenant hadn't failed to notice.
"Go on then, Doctor." He prompted as he dumped his rucksack down onto the floor and fished out his water canteen, taking a large swig from it. "Give us your theory. You're the expert here. What do these things want?"
"Could be anything." The Time Lord replied casually, scratching his head. "Hard to tell when you don't know anything about the species. They could have crashed landed here, the ship becoming buried underground from the impact. But all signs point to them only recently coming to the surface, given they've only just killed someone."
"There weren't any reports of a crash," Stefan said. "If they did, we would have heard about it. But why take someone down here, what could they gain from it?"
"Who knows?" The Doctor replied with a shrug. "For information, or as a hostage. Experiments..."
"Seriously?" Rose gasped. "She must be terrified."
"We'll find her," Peter reassured. "We're not leaving until we do, deadline or no deadline."
This was mainly directed towards Stefan, who nodded in agreement. They were risking more than a telling off if they deviated from their arranged turn around time. UNIT would think them missing in action and mount a rescue attempt, snatching away any chance of a peaceful resolution to the mission.
"It's a brave attitude to have." The Doctor acknowledged. "Can I ask you something, Peter? What brought you to UNIT in the first place? It's not exactly an average job, is it?"
"I wouldn't have suited an average job."
"No, you really wouldn't have." He admitted. "Still though, all those other options out there. Why UNIT? Why choose aliens and danger over everything else."
If Peter was thrown by the question then he didn't show it. There was a hint suspicion in his steely gaze, but otherwise, his face was impossible to read.
"There wasn't much to do where we grew up." He eventually replied.
"Where was that?"
Despite keeping the conversation light, the Doctor could see that Peter had retreated to his default setting of silent moodiness.
In the end, it was Stefan who broke the awkward silence.
"We're from Kent, Doctor." He said. "Milstead village, specifically. It's about twenty miles south of Maidstone. Very quiet, very rural. It's in the middle of nowhere."
"Sounds nice," Rose replied. "It must be a pretty place?"
"It's very boring." Peter corrected. "We both joined UNIT straight out of school. I did my exams and passed through Sandhurst. That was three years ago."
"Sandhurst?"
"Training college to become an officer." The Doctor told her. "Very prestigious and even more difficult to get accepted into. That's before you even start your training."
"Forty-four solid weeks of it," Peter added. "Not for the faint-hearted, I can tell you that much."
"Here's me thinking normal school was hard enough." Rose half-laughed. "What did your family think about you doing that? Do they know about the aliens? My mum didn't even know I was off travelling with the Doctor at first, not till I came back after a whole year away!"
Once again Peter did not look altogether keen on sharing details on his personal life. However, Stefan was only more than happy to keep the conversation going.
"There's just me and my wife at home, Rose." He told her. "Emma knows what I do, and she's okay with it."
"She's a paramedic, isn't she?" The Doctor remembered. "What a wonderful job to do."
"Yeah, she's amazing." Stefan agreed, smiling fondly. "But I've known that for a long time. Me, Emma and Peter all grew up together."
"Oh, childhood romance, was it?" The Time Lord cooed. "What about you, lieutenant?"
Peter's face was sullen at best, and he seemed to think that such a conversation did not belong anywhere, let alone in the middle of a military operation. With a scowl, he leant back against the rock behind him and said nothing.
"Peter, play nice." Stefan chastised him. "Come on, mate."
"You have files on us." Rose pointed out. "You know all about me and the Doctor."
"Very true." The Doctor added with a smile. "So... Come on, Peter. Handsome fella like you, there must be someone waiting for your safe return?"
With even Stefan waiting on him to say something, Peter looked as though he did not have much of a choice but to respond as he let out a long defeated huff of annoyance.
"Yeah, Stefan makes easy work of the whole marriage thing." He admitted with a shrug. "I've just got my parents, and as long as I come home at the end of a mission in one piece then they're fine with what I do."
"Military family, is it?" The Doctor asked. "It's in your blood, so you went out and joined UNIT?"
In an instant, the subject of conversation soured with the lieutenant. His brilliant grey eyes had lost a bit of their sparkle as his strong jawline tensed up from him gritting his teeth.
"No idea." He replied evenly. "I'm adopted."
Even the Doctor could not have missed the marred tone that sprang from his throat.
"Oh, right." He quickly apologised. "Sorry, I didn't know."
"Why would you?" Peter remarked back. "Still, it's nothing to be sorry about."
"Yes, I'm sure they're amazing people. Did you take their name, or..."
"Ha!" Peter barked out. "With a name like Peter Alexander Argent? Not bloody likely, no. There was a scrap of paper with it scribbled on when they found me. Not much of a start, but at least it was something."
Rose suddenly felt awful.
She had never really known her father, only briefly when she had travelled back to 1987 on the day that he had died. But she could have never imagined not knowing anything about who she was or where she came from.
"I'm sorry." She told him. "How old were you?"
"Three months old. Young enough not to know any different of course." He replied. "But it's like I said, there's no need to be sorry. My parents did a pretty good job… All things considered."
As the lieutenant had been talking, the Doctor noticed that he had been fiddling with his ring.
"You weren't just left with a name, where you?" He asked him, pointing at it. "They left you that too, didn't they?"
Peter seemed surprised by this observation.
"Yeah, they did." He confirmed. "How'd you know that?"
"Just a shot in the dark."
"Yeah, well it's not much of clue though, is it?"
"Oh, I don't know." The Doctor told him. "You could still find out? Ask around and see if you can dig up some more information?"
Peter shook his head at this.
"That's impossible, Doctor." He replied with some certainty. "Believe me."
"What do you mean?"
But Peter was already picking up his rucksack and swinging it onto his back.
"Look, I appreciate that we're getting on a little bit better. Sharing stories and all." He told him quite sharply. "But there's a missing woman who isn't going to rescue herself. Come on, break time is over."
For the first time, he maintained his hostile expression as he looked over toward Stefan.
Perhaps aware that he was being blamed for his part in the unwanted conversation, the corporal nodded back and picked up his rucksack.
"Ready to go, boss." He replied respectfully. "Rose, you can follow behind him. Doctor, stick ahead of me."
Hesitantly, Rose followed after Peter as he began to march off.
The Doctor hesitated, however, as he glanced at Stefan curiously. But the younger man said nothing further on the matter, and the Time Lord knew that years of friendship and secrets were not about to unravel just because he was curious.