"Yes, sir." The airman was very fair, pale as a Russian, eyebrows and eyelashes almost invisible. "I'm sorry, Dr. Zelenka."
"Don't be," Radek said briskly, and meant it. "It is better to be concerned and find out that it is nothing serious than to ignore something you can't identify. Do that, and it will certainly be the Wraith. Or worse."
The airman managed a smile at that, as Radek had intended. "Yes, sir."
"Now," Radek said. "Are you familiar with the de-icing procedures?"
"Yes, sir."
"Then let us see you apply them." Radek slid out of the chair, letting the airman take his place, and watched as the younger man called up the program. He entered the parameters quickly and correctly, frowning over his screen, and Radek stepped back. The people he'd like to yell at were Dr. Merritt, suspiciously busy at his screen, or possibly Sergeant Trin. Either one of them should have recognized the pattern of the readings, and realized what they were seeing — they'd both been on Atlantis long enough to know to check for ice before sounding an alert.
Before he could say anything, however, a door slid back on the main floor and Sheppard emerged, heading purposefully for the main stairs. That rarely meant anything good, not at this hour of the morning, and Radek wasn't surprised when Sheppard nodded to him.
"Morning, Doc. Got a minute?"
"Of course." Radek let himself be herded out of earshot of the others in the control room, along the railing where they might be talking about something innocuous. Through the long windows, the aurora was fading to pastel wisps against a lightening sky, thin veils of purple to herald the dawn.
"We have a potential problem," Sheppard said quietly. "Can you access the security cameras without everyone knowing about it?"
Radek paused. "Yes. Or at least they won't know immediately. But once I have looked, anyone who comes after me will see the search."
"That's probably all right," Sheppard said, though he didn't look as though he entirely believed it himself.
"It would be helpful if you had a place you wanted me to look," Radek said. "And a time? A range of times? Or maybe you could just tell me what is going on."
Sheppard gave a crooked grin. "Oh, come on, Doc, nobody ever tells anybody that." He sobered abruptly. "An object has gone missing — a package, about so big." He mimed a rectangle half a meter long and maybe a hand's-breadth wide. "It was in a secure location, or at least what I thought was secure, but someone's taken it. I need to find it before anyone knows it's gone. And that means —"
Radek nodded. "I will keep my mouth shut, of course. Where was this — package — taken from?"
Sheppard looked over his shoulder. "Maybe we could take this somewhere more private?"
"Okay." Radek beckoned to Dr. Merritt, who rose reluctantly from his place. "You're all right with the underwater sensors now?"
Merritt nodded.
"Then I am going to get some breakfast. Next time, it would be better to check the cameras first."
"Yeah," Merritt said. "I'm sorry, Dr. Zelenka, I just forgot."
"Yes, well," Radek said. "Not again, please?" He nodded to Sheppard. "And I am at your disposal, Colonel."
"After you," Sheppard said.
After a moment's thought, Radek took him to one of the smaller system labs, not often used except when they were running full-systems tests on the city. He entered his passcodes and brought the consoles to life, then typed more commands to let himself into the security system. A map of the city blossomed on the screen, slowly rotating, and he looked over his shoulder at Sheppard.
"Okay," he said again. "Tell me where this thing was so I can start to look."
"Here." Sheppard touched one of the smaller southwest towers, just below the top chamber. "I'm guessing you don't have cameras there, right?"
"Right," Radek answered, entering coordinates. "But we do have cameras in the stairwells and outside the transport chambers. When did this happen?"
"That's an excellent question," Sheppard said. "Start with overnight."
"Yes," Radek said, typing that in, and grimaced at the size of the datafeed. "It will take me some time to go through this, Colonel —"
"I was afraid of that," Sheppard answered. "Look, if you find anything — radio me right away, got it?"
"Yes, of course," Radek said, "but it would help if you told me more about what I might be looking for —"
He stopped, realizing that he was speaking to empty air. "Of course not," he said, and frowned at the screen.
Luckily, they had already developed algorithms that could do the preliminary analysis of the footage, but it was still almost an hour before he spotted the first anomaly, and even then it was sheer chance that alerted him. The camera in the ZPM room showed that he had entered the area at 9:19 the previous night for a routine check of the subsystems' direct readouts. Radek touched keys to reverse the image, and played it again, watching himself enter the ZPM room and walk purposefully to the console. The problem was, he hadn't been anywhere near the ZPM room yesterday. That footage — he slowed down the image, zoomed in to look at his own left hand. Yes, it had been taken the day before, there was no question about it. That was the bandage he had gotten in the infirmary after he'd cut his left forefinger reaching into one of the less accessible parts of the Hammond's engines. It was a small cut, and he'd only gotten the bandage so that he didn't bleed on the more sensitive equipment. He'd taken it off again at the end of the day, and the only sign it had ever been there was a tender spot on his finger. At 9:19 last night, he'd been in the shower, not in the ZPM room, and that meant someone had tampered with the security footage.
Once he examined it more closely, it was easy to see what had happened. Someone had erased a section of the security record and replaced it with footage taken on an earlier occasion. It was easy enough to spot once you knew to look for it, and Radek quickly set up a search algorithm of his own to find the all-but-invisible anomalies. He wasn't surprised when the program found three more, and then another, but when it finished its search, he shook his head, swearing softly at the screen.
He touched his radio. "Colonel Sheppard."
There was a brief pause before Sheppard answered, and he sounded faintly breathless. "Yeah, Doc?"
Radek hesitated, not sure he wanted to make this announcement on an open channel. "Do you have a moment?"
"I'm kind of in the middle of something," Sheppard said slowly. "Can you give me the high points?"
"Yes," Radek said. "You asked me to let you know at once if I found anything. I have found gaps."
"Gaps," Sheppard repeated. "Crap."
"Just so."
"How many? And where?"
"More than twenty," Radek said, glancing at his screen. "I am not quite finished with the analysis, but — too many to blame on any normal malfunction. At least one of them occurred in your area of interest, and there are others throughout the city."
"Someone has edited themselves out of the security footage," Sheppard said.
"That is my conclusion," Radek said.
There was a moment of silence, and Radek guessed Sheppard was talking to someone off-channel. "Can you get me locations covered by these edits? Times, too, but the locations are the main thing."
"Yes," Radek said. "I'm already compiling that." He glanced at his screen, checking the progress bar. "Give me another ten, fifteen minutes, and I'll have it ready."
"Thanks," Sheppard said. "I'm sending Captain Cadman to collect it. Don't say anything to anybody else, all right?"