Aghast, Tristan ignored the warning cry and dropped to his knees at his double's side.
"What's going on? What's happening?" The Doctor looked up at him, blue eyes clouded with pain and gasped;
"Empathy…bond... The Sheppa's…final…defence…"
"What does that mean?"
"Get away…save yourself!"
"Not without you." Carefully, Tristan dragged the Doctor backwards and away from the creature until he seemed a little calmer, then laid him down gently. The Doctor spoke again.
"When…the Sheppa…feels threatened…can't run…it can form…a…kind of…tele-empathetic bond…with attacker…projects own pain onto them…magnified by ten times...can't approach…or attack…"
"Can you break it?"
"Only…Sheppa…can break."
"And if the Sheppa dies?"
"I…die." Tristan, now white as a sheet, stood up and looked over towards the black and white shape in the heather. How on earth could they get near it now? And if they couldn't, what then? Would he have to break the news to Tegan and Turlough that… He looked down at the Doctor, then heard the voices of his two approaching companions. He turned towards them, but at his first step, there was an explosion like a feathery firework beneath his feet and a pheasant rocketed up from where it had been hidden in the heather, cackling and whirring its wings in panic. The young man, who had experienced startled pheasants before, stumbled backwards, heart racing. For the Sheppa, this new terror was the final straw. It leapt up, tried to run on the injured leg, then howled in pain and sank back down, unconscious. At Tristan's feet, the Doctor gasped in pain again, then his eyes closed. Alarmed, Tristan dropped to his knees and shook the other's shoulders, but there was no response.
"Doctor?" Tegan was standing at his shoulder with Turlough just behind her. Tristan looked up at them. "He got too close, and the Sheppa formed something called an empathy bond with him. Means that, for as long as it's unconscious, so will he be."
"And after that? Will he be alright?"
"As long as the Sheppa is, then yes." She nodded, tenderly bent down to brush a stray lock of hair from the unconscious Doctor's ashen face, then turned back to Tristan.
"We've got all the stuff from the TARDIS." Tristan had the unexpected, and rather unnerving, feeling that she was expecting him to take charge in place of the Doctor. Why was that? She and Turlough seemed to know more about alien life than him. He was about to question her when James appeared at his side.
"What happened?" Tristan explained the empathy bond quickly, and James swallowed hard.
"Well, I've done enough operations in my time, but they've never been this important. And I don't think I've ever been this nervous, either. You'll help me with the operation, Doctor?" They think I'm the Doctor! Tristan opened his mouth to correct the mistake, then caught sight of the three faces staring at him as if he were their last hope, and it occurred to him how frightened they would be if they realised the truth. As frightened as he was. Unable to bring himself to let them down, he nodded and pulled on the proffered white jacket. Together, he and James spread the sheets on the ground and with infinite care, pulled the Sheppa on top of it. "Give him some of that anaesthetic" murmured James, as if to speak loudly would be to wake the patient; "We don't want him waking up." Tristan poured a little of the mixture onto a mask and held it against the creature's nose, trying to look confident, or at least calm. His colleague was carefully disinfecting the wounds and his instruments, possibly trying to work up the courage to start removing the bullets. Eventually, he turned to Tegan and Turlough, who were sitting by the Doctor's head and watching the operation with hearts very obviously in their mouths. "The leg's broken, and we'll need some clean water to make a plaster cast for it. Could you get some from…wherever you got all the sheets from?"
Turlough scrambled off obediently, and James took a deep breath, looked over at the unconscious man, back to the 'Doctor' and began work on the leg, cutting the wound further to find the bullet, then, after what seemed like a lifetime of painfully careful and slow progress, finding and drawing out the little pellet. There was a complete fracture to the bone, misaligned by the Sheppa's flight, but mercifully, no ligaments or tendons had been torn. He stitched what he could back together, then wrapped it in cotton wool, and began to form a plaster cast with the water.
When the leg was bandaged, although the more serious wound was yet to be treated, the relief was palpable. Somehow, everyone seemed more confident that this was an animal like any other and that it, and the hapless victim of its empathy bond, could be saved like any other. Tristan, for the first time, began to relax and, without thinking, to slip back into his old personality. "Well, at least this patient's a bit quieter than others I could mention, Jim…" As soon as the words were out of his mouth, he realised what he had said. For a moment, Tristan entertained the possibility of trying to rescue the deception and reclaim the Doctor's identity, but he knew it was useless. James sat back on his heels and gazed across at him.
"You're Tristan." It wasn't a question.
"Yes."
"For God's sake, Triss, why didn't you say so?"
Tristan was wishing harder than ever that the ground would swallow him up. "I didn't want to worry you. You all assumed I was him and he- he knew what was going on, and you all seemed so much calmer around him…"
"Didn't want to worry us? You had me thinking that it would only take a slip of my hand, and I'd have to go back to your brother and tell him…" James tailed off, exasperated. "Did you really think that this Doctor mattered so much more than you?"
There was no answer to that. Tristan finally dared to look over at the Doctor's companions, who were staring at him numbly, the Doctor's blonde head looking more vulnerable than ever as it lay pale and unmoving between them in the dark heather. Tegan was the first to speak, her voice unsettlingly quiet. "Save him," she pleaded. Both vets nodded dumbly, and returned their attention to the Sheppa.