oOo

There was a flicker of light ahead and a murmuring sound he was hard-put to identify. After the darkness and silence that marked his descent into the underground caves, both were more than welcome. It had only taken a few minutes to reach the chamber where the Master lay, recovering from his latest almost-death, but the Doctor had never been fond of close, dark places. Especially not with an enemy waiting for him at the end.

Before he even began following the narrow, winding path that led inexorably downward, he noticed the heat. The walls eventually gave off enough warmth that he could feel it through his clothes, on the few occasions he accidentally brushed up against one of the rocky, rough-hewn walls. The light, a sullen red glow that danced and flickered in the distance, appeared to come from a natural source rather than an artificial one. As he reached the point where the tunnel opened up, his suspicions were confirmed; lava flowed in a narrow channel at one end of the largish chamber that now lay before him. Near that flow, lying on a large, flattened rock was the Master.

He was turned away from the tunnel entrance, facing the lava, one arm flung across his face, the other dangling over the edge of the altar-like stone on which he lay. Ace was squatting patiently by his head, her attention half on him and half on the endless movement of the lava only a few meters from her feet. She glanced toward the entrance, saw the Doctor, and gave a small "thumbs up" sign before returning her attention to the unconscious form in front of her.

He frowned and looked around, finally spying his later counterpart crouched behind a largish outcropping of stone about two meters away and several meters closer to the Master than seemed prudent. His other self waved him forward impatiently, and he crept as silently as possible to the other man's hiding place.

It was well chosen, he grudgingly admitted to himself as he reached his destination. What had seemed at first to be imprudently close to the Master's current position was actually slightly farther than it appeared at first glance. Not only that, but there were areas that had eroded enough to afford them a view without having to expose themselves, if they were extremely careful. He assumed it was also close enough to hear the Master's voice, once he regained consciousness and Ace began her task of distracting him.

It was vital that the Master regain consciousness before any of this could work. "If he's recovering from being set on fire," Ace had asked, "then why not just go in there and do your hocus-pocus while he's still out?"

"Because it's his conscious mind we have to affect," her regular traveling companion had replied. "This will only work if he's awake and fully aware of his surroundings. Otherwise, if we catch him in a moment of half-consciousness, or even worse, fully unconscious, we run the risk of failing to fully capture him in the moment, so to speak."

At Ace's blank stare, his earlier self tried to clarify. "We want to trap him in the space between one second and the next, and in order to do so his mind must be focused on a particular moment in time. Even his mind wandering, just for a split second, would keep it from working." For Peri, he remembered bitterly, it had been extraordinarily easy; she was so focused on the idea of traveling with him that he had her complete attention. Exactly what his later self needed to trap her. With a mind as slippery as that of the Master, of course, it would take the concentrated efforts of two Time Lords to do the job.

Not that Ace's job was any easier, nor any safer. She had to keep the Master focused on her, keep his attention fully engaged, while at the same time remaining out of his reach and ensuring that he didn't realize the Doctor was there, in duplicate.

To that end, the Doctor's later self had insisted she pull on a native gown over her own clothing. "Why?" she'd demanded, annoyed at the voluminous beige skirts. "Slow me up, it will; besides, one word out of my mouth and he'll know I'm not from around here."

"True enough, but he'll probably believe you're one of the Trion political prisoners," the Doctor pointed out. "Earth clothes would completely give us away."

So there she was, with the loose folds of the gown gathered beneath her, her hair demurely braided, watching the Master like a hawk, only allowing her attention to wander to the lava flow for the briefest periods of time.

The Doctor's fifth self could hardly blame her; he could barely keep his eyes off it himself. Dangerous and lovely, there was something almost hypnotic about the molten surges, the red glow, the occasional pop or crackle as pieces of the hardened lava that formed the bulk of the cave floor broke off and rejoined the flow.

"Aaaaahhh!" The sudden cry startled them all, and the Doctor's two selves shuddered in sympathy. Even the Master, even their deadliest enemy, was capable of feeling pain, and each of them had suffered through the fires of regeneration enough to recognize that agonized cry as one they themselves might have uttered.

Ace, who had toppled backwards in her own startlement, scrambled back to her feet. Remembering the role she was playing, she stood up and moved cautiously forward. "Oi! You there, you all right?"

The Master groaned and rolled onto his back. His eyes opened, but remained unfocused, his hands clenching and unclenching at his sides. Ace peered down at him, then backed up as he rolled onto one elbow and glared around until his gaze settled on her. "You, girl! Who are you? Where am I?"

"Sarn, of course, where did you think you were?" Ace nimbly avoided his first question, but both Doctors could see the tension in her shoulders.

"Sarn." The Master repeated the name slowly, and the two Doctors watched, barely breathing, as his eyes narrowed in concentration. "Sarn. The fires..." He shuddered, then turned his gaze back to Ace. "Where on Sarn, girl?"

She didn't look happy with his chosen form of address, but managed to keep from commenting on it. "In a cave. I was exploring, and I found you." She looked him up and down critically. "You don't look like a native."

He sat up and swung his feet over the edge. "Of course I don't." The hauteur had never left his voice, even raspy with the heat. "And neither do you, for that matter." His arm shot out and grabbed for her, but she was waiting for just such a move and stepped away, just out of his reach. "Who are you?"

She shrugged. "Just visiting, you might say. Getting ready to go home soon, now that exile's been revoked."

"You're from Trion?" He sounded skeptical, but his attention was fully focused on her now, and the fifth Doctor looked at his future self, who returned the look and nodded in agreement: now was the time.

When the Master moved this time, it was with a speed none of them had anticipated, slow and painful as his movements had been up till now. He was on his feet, pulling Ace toward him by both arms, before either Doctor could blink. She cried out in surprised outrage, struggling against his hold, to no avail.

"All right, girl," he rasped, slamming her against the large stone on which he'd just been sitting. "Tell me, what are you doing here? The truth, this time. Who sent you?"

"No one," she managed to gasp out, glaring at him. "Why would they? No one knew you were here, at least I didn't. Have you come from Trion, are you part of the rescue party?"

Clever girl, putting the questions back on him. Now, if only he would let go of her; they certainly couldn't trap him when he was holding Ace. Not unless they wanted to trap her with him.

The Master opened his mouth to speak, only to snap it shut as a sudden paroxysm of pain shot through him. His grip on Ace's arms tightened convulsively, then he threw her away from him, gasping for breath. "Something's wrong," he said through gritted teeth.

Ace, teetering on the edge of the magma flow, ignored him until her footing steadied. She carefully stepped away from the edge, then turned her attention back to the Master. Who was also returning his attention to her. "You!" he snarled, taking a menacing step forward. Ace started to back away, then realized what she was doing and tried to dodge past him, only to be stopped by the rock. "You did something to me. What was it?" He feinted toward her again, and again she dodged, this time barely avoiding his grasping hands.

She ducked under his arms, cursing as her ankle turned on one of the loose stones littering the cavern floor. Her feet went out from under her as she fell heavily to the ground, rolling toward the edge of the channel while the Master laughed, raising his leg, obviously intending to kick her into the molten magma flowing inches away.

Now! Each Doctor heard the other's voice in his mind as they simultaneously focused on the Master. His foot started to move, Ace scrabbled desperately to get out of the way, and the two Doctors concentrated.

Ace froze. Something was wrong, something was...off. She looked up cautiously, then scrambled to her feet. "Oi! Where'd you go?" The Master had vanished.

"He's still here." She looked for the source of that familiar voice, grinning as she saw the Doctor and his past self stepping around the edges of the stone that had hidden them from view. "Are you all right?" It was her Doctor asking, although she saw an equal amount of concern on the face of his younger self.

She nodded, still grinning, then pulled the voluminous folds of the dress over her head and dropped it to the floor of the cave. "Yah, I'm great," she replied, stepping toward them. Unconsciously stepping around the invisible form of the Master, both Doctors noted, just as she'd avoided the place Peri currently occupied in the Console Room. "Got a really close look at the lava, just like I wanted."

"A little closer than I would have liked," came the tart reply, but she saw the relieved grins on both their faces. "You were brilliant, Ace. Thank you."

"Yes, thank you," his earlier self echoed.

"I still want that trip to Hawaii." Ace grinned. Shaken, but not stirred; that was her, once again coming through a difficult situation with aplomb.

"Of course," the Doctor's later self agreed. "And now that that's been accomplished, I believe it's time we returned you to South Croydon."

"Past time," his younger counterpart agreed. He took one last look around the cave. Ten years. "Are you sure it's safe to leave him here?"

"Perfectly," his later self reassured him. "No geological activity here for the next fifty years. I checked."

His younger self nodded. "Right. Off we go, then." He strode purposefully toward the narrow entrance, and the other two followed, as eager as he to leave.