Blair was slumped in a chair next to Jim's desk, reading an anthropology journal article. The bullpen hummed around him, the noise level ebbing and flowing as the various members of Major Crime went about their duties.

"Here it is," Jim crowed triumphantly as he pulled a sheet of paper off the printer.

"What?" Blair looked up from the article.

"I e-mailed Dr. Price, the woman who was in charge of the Ebola virus when Brackett stole it."

"Sonia?"

"Yeah," Jim rolled his eyes, "Sonia." It still annoyed him that she had chosen to tour the town with Sandburg rather than with him. "Anyway, she never heard of Sean Caine or Marcia Baxter. However, she says your friend Ron McGrath was the computer consultant on a Virology Task Force in Spokane three years ago."

"And that means..." Blair trailed off, eyebrows raised questioningly.

"It means he worked on projects dealing with viruses for the CDC."

"Which means?" Blair continued to look quizzically at his partner.

"Chief, who's supposed to be the smart one here?" Jim ignored the finger Blair flashed at him and continued, "It means he was on a team that had access to restricted viruses."

"And, in the course of his work, he may have been able to 'borrow' one? Maybe that was the background he was referring to."

"Exactly." Jim smirked at his partner. "Told you I could detect."

"Oh, yeah, you're the king, Jim." Blair grinned cheekily as Jim reciprocated the disrespectful gesture. "So where does that leave us?"

"I'm going to arrange to have McGrath picked up for questioning."

"You don't think that will tip our hand?"

"No. Besides, we don't have much of a hand to tip. I'm hoping this will deal us a better one."

"Love the analogy, Jim," Blair said dryly, a smirk on his face.

Jim's comeback was cut off by the sound of his phone ringing. He snatched up the receiver. "Ellison," he said curtly. After listening for a few minutes, he said, "Okay. Pernici's, forty minutes," and hung up. "Grab your jacket, Chief, we've got a meeting."

ooOOoo

Standing at the far end of the counter in Pernici's Deli, Sandburg asked, "So what exactly did he say again?" He began tapping his foot in agitation.

Jim peered around his partner, watching the entry to the warm, bustling deli for Ron McGrath. "I already told you. McGrath said he was hired to work on a virus, but he's now afraid that what he knows is going to get him killed. He said he'd meet us here to talk."

"He didn't say anything about who he works for or why?"

Jim sighed in exasperation. "Sandburg... that's all he said!" After waiting a beat, he snapped, "Stop shaking your foot."

"Okay, okay. Sorry, man. Calm down!" Blair shook his head and watched his partner as they waited. Jim seemed unusually tense. Wondering if Brackett was the reason for that tension, he said, "I just don't like the idea of Brackett hanging around."

Jim glanced at him, then back to the door. "Neither do I, but we have no proof that it's Brackett who's behind these murders, just our suspicions. And Lincoln's involved somehow, too. Hopefully McGrath can shed some light on this."

Blair started tapping his foot again. Jim glared at him, irritated. Blair smiled in an attempt to appease his tense partner and raised his cup, taking a sip of his coffee. Without realizing it, he then started tapping the side of the cup.

Jim was about to swat at his partner's fidgety fingers when the detective straightened. Looking out the wide windows of the deli, he saw Ron McGrath striding toward the door, looking around nervously as he walked.

"There he is, let's go." Jim tossed his cup in the trash and walked toward the door. Blair dropped his cup after Jim's and hurriedly followed.

They were almost to the door when they saw McGrath stiffen, reach awkwardly toward his back with one hand, then collapse with a look of shock and pain on his face. Racing through the door to his side, Jim quickly began checking the limp body. Blair tried to keep back the curious people who were beginning to crowd around them, while simultaneously dialing 911 on his cell phone.

"Is he dead?" he quietly asked his partner while waiting for the operator to respond.

Jim shook his head. "Not yet. Shot in the back. No exit wound that I can find." He shot a meaningful look at his partner, and then returned his focus to McGrath, continuing first aid.

The 911 operator answered, and Blair turned his attention to the call, succinctly requesting an ambulance and police backup at their location. He was put on hold as she dispatched the units.

While he waited, Blair looked down at McGrath. The man was bleeding from the middle of his back. Jim had placed McGrath on his stomach, his head turned to one side, with Jim's jacket cushioning it. Jim had slipped on a pair of latex gloves -- he always kept some with him for collecting evidence. Now he pressed one gloved hand down firmly on the wound to try to staunch the flow of blood.

"Jim?" Blair asked softly, the phone still pressed to his ear. "Didn't you hear the gun?" Blair kept his voice down so the curious bystanders wouldn't hear him.

"I didn't hear anything!" Jim snapped back. "Wait a minute.... Chief, his back feels... cold."

"Jim, c'mon, man, it's wet and chilly out here. Everything's cold!"

"No." Jim shook his head impatiently. "I mean around his wound. The skin is cold where the bullet entered."

Blair looked at him, confused. Before he could ask any more questions, the operator came back on the line, and he focused on providing her with the additional information she needed.

ooOOoo

"It's okay, Jim, there was nothing you could have done for him. His aorta was nicked and he would have bled out no matter what you did." Blair looked around the loft, wishing there was something he could say that would make his friend feel better.

Jim, sitting on the couch, put his head into his hands. "I should have been able to hear something. See something. Warn him or protect him. Something, dammit!"

"You probably did hear something," Blair commented sitting in the chair next to him.

Jim raised his head and looked at him dubiously, cocking an eyebrow.

"C'mon, you know the drill. Let's access that fabulous sensory memory you have." Sandburg reached over and gently pushed the sentinel backward until Jim rested against the back of the couch. "Now, relax, Jim, and listen to my voice."

Jim complied and soon his Blair's soothing voice made the tension lessen and disappear. His muscles relaxed and his breathing slowed and deepened. He easily slid into the trance-like state they had found allowed him to recall sensory details with an astonishing degree of accuracy.

"Now, think back to when we were waiting in the deli," the low, comforting voice continued. "I was talking to you, you had told me to stop tapping my foot. I took a drink of coffee, and then you spotted Ron. You started for the door. What were you hearing?"

His eyes closed, Jim tipped his head to one side, as if he were actually listening now, not remembering something that had happened hours before. "Two women discussing their shopping trip, an argument about the price of a sandwich, and...A couple making out in the back."

Blair snickered softly at the mention of the couple, then suppressed his amusement to focus on the task at hand. "Okay, good. That's good, Jim. Now block out all the people talking and tell me what you heard as we got up to the door, just before McGrath collapsed."

"Food cooking, telephones, lots of traffic, a siren a few blocks away, some road repair equipment, more people talking, and...Something else," Jim frowned in memory. His head tipped a bit more to the side as he concentrated.

"What else?" Blair prompted.

"A hiss. Sounded like an air leak or something."

"That's good, that's good. Anything else?" Blair strove to keep his voice low and even, despite his excitement.

"No! There's no gunshot or hammer being cocked or anything like that." He opened his eyes back up to gaze at his partner. His face revealed his frustration. "Dammit, Blair. A hiss of air? What good is that?"

Blair made a calming motion with his hands. "Okay, Jim, take it easy. I think the hissing noise is important. You picked it up out of all the other miscellaneous clatter around you. We should concentrate on finding out what that was." Blair got up and started pacing the room.

The sentinel leaned back against the couch again. After a moment, he said, "Maybe someone ran over a nail, and it punctured their tire."

"Is that what it sounded like?" Blair stopped pacing for a moment, turning to face his partner.

"Mmm....No....Not exactly." He watched Blair resume his rounds. "We should call the morgue. See if they've found anything," Jim said, changing the subject.

"I can guess they'll say, 'No, there's nothing to find.' Assuming it's the same as the others, which it sure seems like it is." Blair plopped back in the chair, face crunched as he thought about his friend's death. "Damn. Ron was a nice guy, too. He helped me with that program." He shook his head and buried his face in his hands. "Man, we told him to trust us, and look where it got him."

Jim took a deep breath, studying Blair carefully, not quite sure what he could say to ease the young man's burden. He knew it was difficult for Blair when someone died, especially if he had known the person. Shaking himself from his thoughts, Jim stood and moved to the phone, briefly resting a hand on Blair's shoulder in silent support as he passed him.

While Jim called the station, Blair again stood, walking over to the balcony and looking pensively out over the city.

Jim joined him a few minutes later, standing close enough that their shoulders just touched. He, too, looked out over their city.

"Any luck?" Blair finally asked when Jim remained silent.

"No. No bullet, no nothing. Just like Caine and Baxter. The lab reports have started coming in from those two, though. They detected minute amounts of an as-yet-unidentified chemical in the tissues surrounding the entry wounds. They're working on figuring out what it is. It might help us understand how they were killed."

Blair glanced at Jim then turned to look outside again. "Do you think he's still out there?" he asked, his voice hushed.

"Who? Brackett?" Jim felt Blair nod next to him. "I'm sure he hasn't given up on whatever scheme he's cooked up. I just hope we're able to find the answer before we lose any more people. Come on, Chief, we'd better get some sleep." He draped his hand around his friend's shoulder as they turned away from the balcony doors, again lending him his support.

ooOOoo

Blair peered past the windshield wipers that were valiantly trying to keep the window clear of the omnipresent rain. "Uh, Jim, I thought you were going to drop me off at Hargrove Hall. Why are we back here?" he asked as they pulled up to the Biomedical Lab once again.

"Lincoln is central to all this, the common factor in all the murders. We have to figure out what the key is."

"Well, we've got to hurry, man. I have a meeting in forty minutes."

As they walked toward the entrance of the lab building, rain slid down under Blair's collar, tracing a cold, wet trail down his back and making him shiver. It reminded him of the too-cool shower he'd taken that morning. Jim had used more than his share of the hot water -- again. He looked appraisingly at Jim, his eyes narrowed and his lips curling slightly in irritation. "Hey, Jim, you suppose they'd rent me a lab or something, cheap?"

Jim looked at him, confusion written in the lines on his face.

"Well, it's a lab, they've got to have showers, right? And I'll bet they don't run out of hot water here!"

Jim gently swatted the back of Blair's head, shaking water droplets loose from his damp curls. "Let's go, funnyman," the detective said as he held the door open.

The receptionist saw them coming and swiftly picked up the phone. After speaking quickly, she hung it up and faced them. "At Dr. Lincoln's standing request, I've called security, gentlemen, so if you will leave now, there will not be a problem."

"I don't see us having a problem, ma'am," Jim responded coldly. "This is an official police investigation into two -- make that three -- murders. I'll speak to whomever I need to, and your security people will not hinder me, or I'll arrest them for interfering with a police investigation. Furthermore, if you interfere, I'll have to arrest you as well. Now, I just want to discuss something with Dr. Lincoln. Let him know we're here, will you?"

Gulping, she seemed to shrink in on herself a bit. "I'm afraid he's not here. He hasn't come in yet this morning."

"Well, Ms. Perkins," Jim said, glancing at the name plate on her desk, "maybe you can help me." Jim turned slightly and acknowledged the two security guards who had come to stand behind them. "Gentlemen. I'm Detective Ellison, Cascade PD." He flashed his badge. "I'm investigating a series of murders. I trust you won't be interfering?" He gave them a cold look and turned back to the woman. The guards glanced at the receptionist and then at each other. Finally they stepped back a few feet, evidently not eager to cross the police detective.

The receptionist gave the security men a dirty look when they backed away, then turned to Jim. "Well, what is it?" she snapped defensively.

The detective opened the file folder he was carrying and brought out a picture of the first victim. "Do you recognize this man?"

After giving him a suspicious look, she glanced at the pictures. Then she wrinkled her brow and her entire demeanor changed. "Why, yes, of course. He's a researcher for Mr. Lincoln's project," she stated, puzzled.

Blair glanced at Jim, then at Ms. Perkins. "You mean Sean Caine worked here, too?"

She looked up at the two men and said, "Well...yes. He works in Lab D, although come to think of it, I haven't seen him for a few days."

"Do Marcia Baxter and Ron McGrath work in Lab D as well?" Jim questioned, pointing at the other two pictures he had put on the desk.

"Why, yes. Yes, they do. What is this all about?" She was starting to look a bit concerned. Remembering that the detective had mentioned three murders, she finally seemed to realize that these three people in the pictures must have been the victims of the murders. Her face paled suddenly, and she sank back into her chair. "You mean they were...they were the ones who were killed?" Her voice was a whisper.

"Are you all right, ma'am?" Jim asked.

"Um, yes, yes, I am," she said softly. "I just, I didn't know...."

"Ma'am?" It was one of the security men. "Do you need us any more? It's time for us to make our rounds."

She shook her head, "No, everything is under control. Thank you for coming." The security guards disappeared around the corner, leaving the three alone in the lobby.

Blair had moved around the reception desk when the woman had paled. He kneeled next to her and gently patting her hand where it rested on the arm of her chair. "Are you all right, Ms. Perkins?"

"I will be. Thank you, young man. It's just such a shock. It also explains--" She suddenly stopped talking, as if afraid of revealing something she shouldn't.

"Explains what, Ms. Perkins?" Jim encouraged, his voice low and non-threatening.

"Well..." She paused, glancing down where Blair was patting her hand. She looked into Blair's sympathetic eyes, then back up at the tall detective. "Matt--Dr. Lincoln--has been rather...stressed lately."

Jim nodded slightly, continuing to look steadily at her.

"I mean, well, he's been gone for long periods of time lately, and normally he practically lives here." She took a deep breath, and continued. "And when he's been around, he's been edgy. Nervous, you know? Looking over his shoulder, that kind of thing. He's been sending and receiving a lot of faxes, too. I normally don't see his faxes, of course, but his machine went on the fritz for a few days, and he asked me to handle his 'in and out' faxes until it was repaired," she explained.

"Do you have any idea what the faxes concerned, ma'am?"

She squirmed. It was obvious that she knew something, but was uncomfortable admitting that she had looked at information she shouldn't have. "Um..."

"Ma'am, it's important that we know what you've seen. Someone has killed three people already. We want to stop them before anyone else is hurt. Please, what were the faxes regarding?"

"Well, they were about a virus." Her voice was so low that Jim wouldn't have heard her if not for his sentinel hearing.

"A virus? Like the Ebola virus?" Jim asked sharply, exchanging a quick look with Blair.

"No! Oh, no, nothing like that!" She seemed appalled that he would even consider such a thing. "A computer virus."

"A computer virus?" Jim looked doubtfully at Blair.

"Could be valuable, Jim. Depends on what it does," Blair said, as if reading Jim's thoughts. "It could be designed to extract and transmit confidential information, such as industrial secrets, for example."

Jim thought for a moment then nodded. "Okay. Ma'am, do you know who he was exchanging faxes with?"

"No, not offhand. He just gave me phone numbers, not any names."

"Can we get the records of those faxes? We can trace the phone numbers, find out who he was in touch with."

"Certainly," she said crisply. She rose and moved over to the credenza where a copy machine, printer, and fax machine sat. Efficiently pressing the appropriate keys, she produced a report of all fax calls in and out for the previous month. "This should cover most of them," she said, handing the sheet to Jim.

"Thank you, Ms. Perkins. Chief? I'm going to call Simon, let him know what we've found. Excuse me, ma'am," he said, nodding to the woman as he stepped away from the desk and punched a button on his phone.

Blair turned his most reassuring smile on the receptionist, telling her that they really appreciated her help. They could hear the murmur of Jim's voice as he spoke on his cell phone.

"Well, sure. I mean, someone killed them...." Suddenly she stiffened slightly and asked, "What about Nick?"

Jim, alerted by the sudden change in her posture, pulled the phone away from his ear. "Who?"

"He's the other researcher on the project, isn't he in your files?"

"Simon, I'll call you back. Okay, sir." Tucking the phone in his pocket, Jim stepped up to the desk again. "No, his name hasn't come up yet. What's his full name?" Jim pulled his notebook and pen out, setting the pad on the counter.

"His name is Nick Isacks, and he works at Geiger Electronics on Federal Avenue."

Jim nodded when Blair murmured, "Caine."

"Can you give us his address, phone numbers, some way to contact him?"

She looked uncertain about whether she should give out personal information, even if it was to the police.

"Please, Ms. Perkins. Mr. Isacks' life might depend on our finding him before the murderer does."

She gulped, then turned and pulled out a file. Flipping through it quickly, she located the information on Isacks. She pulled the card and put it in the copy machine, punching the COPY button quickly. She handed the copy to Jim and re-filed the card.

"Thank you, Ms. Perkins. Someone will be contacting you for your statement. Will you be here for the next couple of hours?" Jim tucked his notebook and the folded papers she had given him into his jacket pocket.

"Yes, I work until 5:30."

"Okay, thank you again. Here's my card in case you need to reach me." He set it on her desk. "Come on, Chief." Jim turned to leave.

Blair stood, patting the woman on the shoulder. "Thank you so much. We'll be out of your hair now." He smiled again at the woman.

She smiled back, and then looked at Jim. "Detective?"

Jim halted, turning to look at her again. "Yes?"

"Dr. Lincoln's always been somewhat...ruthless in getting grants and such, but I never thought he'd take it that far."

"We'll find out what happened, Ms. Perkins. Don't worry." Jim smiled at her, his previously stern face softening. With a departing nod, he turned and headed toward the exit.

Blair walked alongside Jim, hurrying his pace to keep up. "Okay, well, I've got to get to my meeting, man. Think you can handle this from here?"

"I'll try to manage, Sandburg," Jim said dryly. "I'm heading over to Geiger Electronics to have a talk with Mr. Isacks."

"Good luck. I'll catch you later. And, Jim? Be careful, man."

ooOOoo

Two hours later, Blair was leaving Hargrove Hall. He heard his name being called and turned to see Jack Kelso wheeling along the sidewalk toward him.

"Hey, Blair! How's the investigation going?" the professor asked when he was close enough.

"Pretty good. We found out all the victims worked at the Biomedical Lab on a project together. Jim's hunting down the last of the group."

"That's good news. Have you figured out who the killer is?"

"We thought at first that it was Brackett, but now we suspect the guy who's heading the project, a Dr. Matthew Lincoln."

"Don't know him," Jack said, shaking his head slightly.

"Well, we're in the process of trying to pin down a few more details, then I think Jim's going to get warrants for his arrest and to search his lab."

"I'm glad you're making progress on the case."

"Well, we think we've got the motive and the murderer, but we still haven't been able to figure out how the killer is doing it."

"What do you mean?" Adjusting the satchel resting in his lap, Jack tilted his head as he listened.

Blair quickly explained the circumstances surrounding the "unexplainable" deaths, and the apparently vanishing bullets. He even mentioned his earlier comments to Jim about the Dick Tracy ice gun, with a self-deprecating grin. He trailed off when he saw Kelso's expression. "Is something wrong, Jack?"

"I hate to say it, but that sounds awfully familiar. You got time to come to my office?"

"Hey, if it'll solve this case, I have nothing but time." Blair tightened his grip on his backpack as they turned toward Jack's office.

Kelso looked warily around the campus grounds as they started toward the Poly Sci building. "Have you heard any more from Brackett?"

Blair shook his head angrily. "Jim caught him spying on us, but he got away. We haven't seen or heard from him other than that."

"Well, as they say, that may be good news."

"Yeah, that's what they say." Blair didn't sound convinced. A few minutes later they made their way up the ramp to the door of the Poly Sci building. Blair held it open as Jack wheeled into the brightly lit hallway.


ACT IV