"What the dogs did, Dr. Scarpetta, "she began, picking at her salad. " Can you offer an interpretation?"

I could, but I did not want to.

"Obviously, the one dog got upset. But the other one didn't?"

Her observation was posed as a question.

The other dog, Salty, had indeed reacted very differently than Neptune had. After he sniffed the driver's seat, Gail hooked the lead on his harness and commanded, "Find."

The dog took off like a greyhound. He snuffled across the exit ramp and up through the picnic area. Then he tugged Gail across the parking lot toward the Interstate and would have gotten a nose full of traffic had she not yelled, "Heel!"

I had watched them trot along the wooded strip separating west lanes from east, then across pavement, heading straight for the rest stop opposite the one where Deborah's Jeep had been found. The bloodhound finally lost the scent in the parking lot.

"Am I to believe," Mrs. Harvey continued, "that whoever was driving Debbie's Jeep last got out, cut through the westbound rest stop, and crossed the Interstate? Then this person most likely got into a car parked in the eastbound rest stop and drove away?"

"That is one possible interpretation," I replied, picking at my quiche.

"What other possible interpretation is there, Dr. Scarpetta?"

"The bloodhound picked up a scent. As for the scent of who or what, I don't know. It could have been Deborah's scent, Fred's scent, the scent of a third person - "

"Her Jeep was sitting out there for hours," Mrs. Harvey interrupted, staring off at the river. "I suppose, anybody could have gotten in to look for money, valuables. A hitchhiker, transient, someone on foot who crossed over to the other side of the Interstate afterward."