A/N : thank you everyone for following me with this! :)

Peter hung up his phone, sighing. They still had no clue about how the now five victims had died, and Olivia's cravings for sugar did not seem to be a symptom for any poisoning, according to Walter.

Her head ached, although less than it did when she had woken up. She had managed to eat quite a lot, copiously mixed with what seemed to be very sweetened coffee. She did feel somewhat better, even though the previous night seemed mixed up with her dreams.

"What's going on?" she asked tentatively. They hadn't spoken since her outburst.

"The police found three other bodies. Walter had a theory but it all went to the trash with those new victims. Broyles is sending us the files so we can have a look at it." Olivia nodded and logged onto the computer, waiting for the incoming mail. A few minutes later, everything was printed and laid on the desk between them.

"Three brothers?" Peter asked. "Mathew, Jamie and Lonnie Boyett. 23, 25 and 26 years old. It says here there's a fourth brother, Andrew."

"I'll ask Broyles to locate him." Olivia grabbed her phone and talked to her superior for a few minutes. He wondered how they were holding up, knowing how tense it was between the FBI agent and the consultant. Olivia was his colleague, but also his friend, and it pained him to see her in such a disarray.

"So far, nothing. Walter is running tests already, but his first conclusion is that they all died the same way. How? He doesn't know yet."

Peter and Olivia worked on the files all morning long, trying to find clues that would tie the victims, studying their whereabouts, their hobbies. Nothing linked the victims, and the house in which the three brothers had been found was a dead end. Andrew was still missing, and had been reported absent from class for a week prior to the death of his brothers. He was either hiding, or had suffered the same fate as his brothers.

Peter noticed Olivia was weakening as the hours passed, her face looking paler. She began to ague that she was fine, but Peter all but forced her to lie down and rest.

"I won't say you look terrible, but you should rest as much as you can." She complied and took a nap, but not before commenting. "You look like hell, too. And you could use a shower." Peter smiled at that and put the cover up to her shoulders, brushing her hair back from her eyes.

Meanwhile, Walter had extracted tobacco and a lethal level of cyanide from each of the five victims' blood. The problem was, the Boyetts didn't smoke. No cigarette had been found on the corpses, or back at their apartment, and their fingers held no stain. The cyanide had been ingested by all, but not the same way. Astrid and him finally took a lunch break, meeting Broyles to inform him of the new development.

The afternoon was spent by Olivia on the couch, sleeping. When she woke up, she didn't see Peter in the room, and immediately sat up.

"Peter?" Nobody answered. Standing up, she saw him though the plastic windows he'd put up, bending over what she believed was Walter's latest experiment. The one that had exploded. The one that had probably contaminated her.

"Peter! What are you doing? Come back here!" He looked up and quickly walked back to the office, not wanting her to get out and risk getting worse. He took off the handmade cloth mask he'd been wearing, getting ready for the blow.

"What the hell were you thinking? Walter said to not go back near those test tubes!" Before he could answer, Peter fell on his knees, trying to loosen the collar of his shirt. Breathing heavily, he fell onto the floor, suffocating.