Decker smiled and told him to go on.

“Janie says she’s never worked with Marie—she works in one department, Marie works in another. But for years they’ve been doing the same shifts, and the same overtime shifts. Soon they notice they’re always parking cars at the same time and walking into the hospital at the same time.”

Harlow sucked in his belly.

“To make a long story short, as long as Janie and Marie always seem to be together anyway, they decide to walk in and out of the lot together. You know, like protection. ’Cause these underground parking structures are stewpots of crime. So each one waits for the other for about five minutes. If the other doesn’t show up, the one who’s left goes in solo.”

“So it’s an informal kind of thing?” Marge asked.

“Seems that way,” Harlow said. “Naturally, my guy asks this Janie if she and Marie walked in together last night. She says yes. Lucky break with a capital L. My officer tells me, then I ask Janie where’d she and Marie park their cars. I figure we can maybe pull a tire print or something from the empty space. Boom, I find this!”

“Good work, Brian,” Decker said. “Let’s get a lab man down and see if they can get a clean sample of blood.”

“Gonna be hard,” Harlow said. “All sorts of crap on a garage floor—oil and grease with the grime.”

“The lab should have cleaning emollients. Hopefully, they’ll be able to precipitate something decent. If we can find prior blood workup on Marie Bellson, maybe we can do a rough comparison and see if there’s a basis for a match.”

Marge said, “We should see if there was blood work done on the baby, too.”

Decker made a face. It was a horribly gruesome thought, but Marge was right. “Go ahead. And while the lab is out here, try to pick up a tire print. Marie could be savvy enough to change the plates on her car, maybe even spray-paint it a different color. But most people don’t think about tire prints. Also keep an eye out for shoe prints. Lots of grease around here.”

Harlow said, “How’re you going to find blood work on Bellson?”

“I’ll see if she has a private doctor,” Decker said.

“Maybe she’s been a diligent health professional and has had a yearly checkup.”

Marge said, “Maybe she’s had surgery done at the hospital. If so, she’d have a chart here.”

“Good point,” Decker said. “Get someone to check the chart room.” He stuck his hands in his pockets. “I’m on my way to Bellson’s apartment. Call me through the RTO after you’re done with the scene.”

“Sure thing.” Marge stared at the blood spots. “I don’t like this.”

“It does get the heart going,” Harlow said.