He couldn't breathe.

His lungs were laboring desperately for air, but there was none to be had. He was going to die here, with a shuttlecraft for a coffin, never seeing his wife and children again. Never seeing Geordi again. Unable to see anything or anyone that mattered to him as he died.

He realized that wasn't precisely true. He could choose to die looking out at the stars he'd made it his life's work to explore. He could die looking into the vast depths of space.

With a violent, wrenching effort, he turned his head and gazed out the viewport.

The stars were the last thing he saw before the blackness took him.

*****

Daystrom Soong expected to be dead. It was something of a shock, therefore, to open his eyes and find himself in the Enterprise's sickbay. A few feet away he saw a familiar, blue-gowned figure. She was facing away from him, studying a computer padd, but there could be no mistaking the red hair spilling over her shoulders. Dr. Crusher, he thought with a surge of relief.

He hadn't died after all. They must have gotten him out just in time.

"Doctor—" he whispered. Even to his own ears his voice sounded faint, hoarse, and he realized his throat was sore. Too much gasping for air, probably. He had a hell of a headache, too. Must have slammed his head against something. Good thing his skull was so hard.

Despite the pain, he managed to lift his head slightly and tried again. "Doctor."

Crusher turned around. "Well," she said. "You're awake."

Day flashed her a rueful grin. "I guess I was lucky," he said.

"You might say that," Crusher said. "Then again, you might not."

What the hell did she mean by that? He didn't like the way she was watching him, with the kind of cautious look he'd seen her reserve for Romulans and Borg. He got the distinct feeling she had some bad news to impart, like he'd lost a limb or something. Crusher had never had much of a poker face.

His heart rate climbed, and he heard the monitor over his head start beeping. "I thought I was dead."

"You came pretty close. You were without oxygen longer than we would have liked. I was afraid you had some brain damage."

"But I don't. Do I?" He couldn't see how that was possible, because he felt perfectly normal. Sure, his head felt like it was on fire, but his mind was clear. He knew perfectly well who he was and where he was.

Crusher paused for a long moment. "No. You've got a concussion, and you've been out for a long time, but you seem to have come through it well enough."

And yet she still looked at him as if she was trying to bluff with a pair of threes in her hand. There was something else she wasn't telling him, he was certain. "But?"

"I think you need to talk to the captain."

"The captain? Beverly, what the hell is going on?"

Crusher turned away from him and hit her combadge. "Captain," she said to the air. "He's awake."

"On my way," Picard's crisp tones replied.

Crusher shot Day one last, uneasy look and moved away from him. He tried to sit up and go after her, demand that she explain what was going on, but he couldn't seem to move his body. At first he thought he'd been paralyzed, and an icy fear gripped him. But in a moment he realized he could feel his legs perfectly well.

He was being restrained by a force field.

Were they afraid he was going to hurt himself when they told him whatever news they had? Good God, had something happened to Tasha or the girls? He felt himself break out in a cold sweat. The monitor beeped, and he forced himself to breathe deeply, to slow his pounding heart.

The doors to sickbay opened, and Picard strode in.

"Captain," Day gasped. He took another deep breath and forced himself to speak more evenly. He had to be calm. He was second-in-command of this vessel, and hadn't gotten to that position by panicking. "Captain. What's going on?"

Picard walked toward him. On his stern face there was an expression of caution, of wariness, that mirrored Crusher's. He paused at Day's side.

"Who are you?" he said.

Day felt his mouth drop open. Whatever he'd expected, that wasn't it. "I beg your pardon?"

"I asked for your name."

Day felt the universe wobble, then steady, as he began to understand what was going on. Picard was just trying to make sure he knew his name and rank. A typical question to ask someone who'd received a blow or two to the head, although he couldn't quite work out why Crusher wasn't the one asking.

"Commander Daystrom Soong, Executive Officer, Enterprise 1701-D," he said crisply. He gave Picard a wry smile. "May I please get up now, sir?"

"No." Picard looked down at him and did not return the smile. "My executive officer is Commander William Riker."

Commander William Riker, the first executive officer of the Enterprise, had died some five years earlier. That's odd, Day thought. I'm the one who hit his head, and yet he's the one who's losing his mind.

Which was, of course, ridiculous. It was impossible to imagine Jean-Luc Picard out of control of his own mind. Picard was the sanest person he'd ever known.

Panic and confusion clawed at his chest, but he struggled for a calm tone. "I'm afraid I don't understand, sir."

"I know you don't, Commander. Tell me about the anomaly you were investigating."

Did Picard think the anomaly had somehow affected his mind? "Uh..." he said, then forced himself into professional mode. "It appeared to be a spatial anomaly, rather than temporal. Lieutenant Commander Maddox thought it might be a kind of bridge, a gateway, between two..."

His voice trailed off as a horrible suspicion occurred to him. Picard offered a faint smile that held no trace of humor.

"I see you are beginning to understand."

"No," Day said faintly. "It can't be."

"I'm sorry, Commander. But it appears that you traded places with your counterpart from this universe."

"You mean I've switched universes?"

"I'm afraid so, Commander."

The panic was back. It slammed into him with the force of a phaser blast, knocking the breath out of him. It couldn't be. It just couldn't. He had responsibilities. His family. Tasha.

He closed his eyes for a long moment, then opened them and stared at Picard. Never in his life had he felt so helpless, and he focused on Picard as if the man were a lifepod, the only thing keeping him from drowning in vacuum. Maybe this wasn't his Picard, but the firm resolve in those eyes was the same.

He had served under Jean-Luc Picard for five years, and he trusted the man with his life. Somehow, by hook or crook, Picard always managed to escape every disastrous situation he got caught in. If anyone could get Daystrom out of this horrendous mess, Picard could.

"You have to help me," he said in a harsh whisper. "Please. You have to help me get home."