Lance observed the scene at the Jeffersonian calmly as he waited for the chance to talk to the woman. There were still chunks of concrete adhered to some body parts that Arastoo was working on dislodging. Brennan was with Booth, they found the company that owned the concrete mixer and were headed out to talk to the owner. Apparently the driver was the one who found the bodies after checking in at a weigh station on the expressway and coming in far underweight. He wondered briefly if the company had security cameras outside. That would make the job far too easy. He glanced at his phone and decided to wait in his office. He was feeling foolish standing around with everyone working. Obviously he could be talking to the woman while Cam picked all the body parts off her, but something told him that she would not be responsive. Something told him that coming across as an impatient, blustering cop would not help in this situation. Perhaps it was his psychological mojo, as Booth might say.

Almost as soon as Lance stepped into his office his cell phone rang.

"Dr. Sweets."

"Sweets, I'm coming to pick you up. I need you for an interrogation."

Lance threw his hands up. "Aren't you with Dr. Brennan?"

"Yeah she's gotta get back to the Jeffersonian to look at some bones they cleaned. This one might need a more delicate touch, which is why I called you."

"All right." Lance hung up.

Once inside Booth's vehicle, he found Booth on the phone with the Jeffersonian. Hodgins had found particulates on the bodies belonging to the Eastern Prairie Fringed Orchid. A rare wildflower. So rare that the only place in the area where it grows was next to a small airport. It was a small airport; only single-engine planes and helicopters could fly in there. Also it hadn't been used in three years. The only people who went there were botanists who cared for the wildflowers. Lance turned to Booth after the phone call ended and asked why he was needed to go visit an abandoned airport.

"It's not the airport we're going to visit, it's the trailer park across the street. This park is the only residential place for miles. You see, a manufacturing plant closed down five years ago, and mostly everyone moved."

Lance nodded. "Except for the people who couldn't afford it. The ones living in the trailer park."

Booth snapped his fingers. "Exactly. So we've got to knock on a few doors and figure out if someone saw something. Because there's no way those wildflowers could get into that cement unless the killer was at this airport at some point."

"Concrete," Lance said absentmindedly.

"What?"

"Oh, well, cement is an ingredient in concrete. The flowers were found in the concrete, not the cement."

Booth shook his head. "Yeah, okay, concrete, cement, they're the same thing."

Lance thought about arguing back, then decided against. "Yeah, sure, totally."

Pulling into the airport, Booth pointed out tire tracks.

"I know the squints will want to measure each track before determining if it's the same treads as the mixer where we found the bodies, but I'm gonna say that those tracks look like they belong to that mixer."

Lance nodded. They drove across the landing strips, following the tracks. They led across the landing strips, up to a river. Then the marks were gone. After getting out of the vehicle and walking around, Lance found the wildflowers that Hodgins was so excited about.

"Well, those botanists are not going to be happy about this." Lance gestured to the trampled flowers.

Booth shook his head. "No, they are not. But the squints will be." He texted the Jeffersonian to tell them to send a team out. "Well, let's go talk to the trailer park."

After speaking to everyone at each mobile home that faced the airport, Booth and Lance were at a dead end. Nobody had seen anything.

Booth kicked at a flattened basketball in the road at they walked back to Booth's SUV. "Nothin'," Booth declared. "How can someone not hear a cement mixer barreling through?"

Lance shrugged. "Well, most of the people here work third shift. I'm going to assume whoever stole the truck to put the bodies in thought it would be best to operate at night. So most of these people weren't even home. And I think a few that we spoke to were definitely drug addicts, completely non-reliable sources. Maybe the killer knew that." He paused as they walked up to the vehicle. "Hey, wait a second. Look. All the trailers here are directly behind the ones next to the road. Except for that one." He pointed. "That one is in between, so they might have seen something."
"It's worth a look." Booth turned and walked toward the trailer.

The girl who answered the door looked young. Booth introduced himself and Lance and explained why they were there.

"Yeah, I did see the big truck there a few days ago. When it pulled out the headlights shone right into my bedroom and woke me up."

Booth and Lance looked at each other.

"Do you remember the exact day and time?" Booth asked.

The girl cocked her head to the side. "Let's see. It must have been Tuesday night, because I have to wake up early for a class on Wednesday, and I was so mad that the lights woke me up. Around five a.m. I think."

Booth and Lance thanked her and began walking back to the vehicle.

"Wednesday at five a.m. the mixer pulled out. I think we can assume that was after the murders occurred." Booth sighed. "We don't have time of death yet, but at least now we know it was probably before the truck pulled out of this airport."

Lance smiled. "Right, but we still need the team at the Jeffersonian to gather evidence that the bodies were even here. Right now we only know the truck was."

"You know, the concrete company never reported a stolen mixer. That means the killer was able to take it and return it without anyone noticing," Booth said.

"Unless the killer is the driver, and he was supposed to be out on a normal job," Lance replied.

"Yeah," Booth agreed.

"There's one thing that been bothering me, since we discovered those tracks." Lance rubbed his chin. "If the killer was trying to dispose of the bodies by putting them in concrete, why go through all the trouble of using a concrete mixer? Why not just lay the concrete down himself?"

Booth nodded and stared off into space for a minute. "Because he didn't want to dispose of the bodies. He wanted them to be found."

Lance wrinkled his forehead. "So the woman found alive, that wasn't a mistake. That was intentional. This killer is sending a message to someone."

Booth clapped Lance on the shoulder. "Told you you'd want this case!"

Lance nodded. "Yeah, and now I've really got to talk to the woman."