when steve came to, he was outside the tank. he was tired and did not feel like walking. nevertheless, he walked. at first he did not understand. he thought: i will sit down and rest.
his body failed to obey, continued walking.
"we share this body," the voice whispered to him, within his skull. "you are merely an observer as long as i am awake. i am in control. henceforth, i dwell in this body."
"i want to sleep."
"you will learn that your mind can sleep while your body does not. and the body interests me, human. the body is capable of strong emotion. i want to feel that emotion."
the place, steve realized later, was a sort of proving-grounds. he felt himself walking, walking. he reached the edge of a cliff, stared down from giddy heights. he felt himself teetering on the edge, saw jagged rocks far below him. he jumped. he did not want to, but he jumped.
"we'll be killed!" he cried, icy fear making his heart pound.
"that is fear," said the voice in his skull. "that is wonderful fear. so strong—"
something cushioned their fall, slowly. it was that, steve knew. their fall, not his alone. for the creature shared it with him.
he tumbled, but slowly, like a feather, like a wraith of fog. he alighted on the rocks with hardly a jar, cushioned by some advanced application of a force-field. a large cube of metal was there to convey them to the top once more.
after that, he became giddy. he did not know why, but the impulse to laugh was too strong to resist. he laughed until it grew painful, laughed until the tears came to his eyes.
"that is joy," said the voice. "i can instill joy in you. but the way you express it, that is unique. more!"
and steve's laughter bubbled up insanely again. the creature was wrong—not joy. hysteria, more nearly. unused to emotions, the creature could not tell them apart.
something grabbed his arms and held it. a giant vise which could crush and twist. he saw nothing, realized that it was some mental trick—but thoroughly effective. his arm was being wrenched from its socket, slowly, terribly.
he clenched his teeth, groaned. from somewhere far off, the voice laughed calmly. "i like that. oh yes, i do. i like your reaction to pain."
an intense loathing he had never before experienced took hold of him. at first he thought it was another trick, but he could sense alarm in the creature which shared him. the loathing, then, was his body's reaction to its parasite. almost, he could feel the creature squirming, and he gave free reign to the emotion.
"stop!" the voice was strident, alarmed.
i hate you, steve thought intensely. i hate you.
"stop! i warn you, you will kill us with that, or drive us insane."
vertigo followed the loathing as the creature fought back. steve was tired, suddenly more tired than he'd ever been. he sank back into blackness, knew even as his senses fled that his mind alone would sleep, not his body. with two minds, the body would not sleep at all—and in a matter of months it would perish of fatigue. but the creature within him feared his hatred, and that he must remember.