“What’s nine times six?”

“Fifty-four. Oh, I see, left-brain function. I’m good with numbers.”

“Recite the alphabet backward.”

Concentrating, she began. Twice she fumbled, backtracked, hesitated, but the music and color never faltered.

“Are you ticklish?”

Suspicion flickered over her face. “Why?”

“I want to try a physical distraction.” He squeezed a hand on her knee, made her yelp and jolt, just as Ripley and Zack came through the door.

“What the hell is going on?”

Hearing Ripley’s voice made Mac wince and curse himself for not paying attention to the time. Then, realizing he still had his hand on Nell’s knee—and her husband was armed—he quickly removed it.

“Um.”

“From the looks of it,” Zack said with a wink at Nell, “this guy’s making time with my wife.” As Lucy had come into the house with him, he leaned down casually to rub her head as she sniffed the air and batted her tail. “I guess I have to take him outside and kick his ass.”

“Get in line,” Ripley said and reminded Mac that she was armed as well.

“I, ah. . . Nell agreed to participate in a couple of tests,” he began.

“That’s not quite true,” Nell corrected, and succeeded in making all the blood drain out of Mac’s face. His sudden stricken look made her whoop with laughter. “I volunteered to participate.”

“Would you mind turning off the entertainment portion of your little program?” Ripley said coolly.

“All right.” Nell closed the spell, and there was a moment of complete silence.

“So . . .” Zack began to strip off his coat. “What’s for dinner?”

“You can help me with that.” Nell spoke brightly. “As soon as I’m unhooked from these things.”

“Oh, sorry. Let me . . .” Mac started to reach for the electrodes monitoring her heart rate, then pulled his hands back as if he’d burned them. “Nobody’s going to shoot me in the back, are they?” he asked Nell.

“I can promise Zack won’t. He was just teasing you.”

“He’s not who I’m worried about.” As delicately as possible, he unhooked her, and kept his gaze discreetly averted as she buttoned her blouse again.

“That was fun,” Nell said as she got up. “And informative. Zack, why don’t you give me a hand in the kitchen? Now!”

“All right, all right. I hate missing the fun,” he complained as she dragged him off.

“Okay, Booke, why don’t you try explaining to me why I shouldn’t start swinging?”

“Because violence is never a sensible solution?”

Her answer to that was a low, dangerous growl. He stopped shutting down his equipment and turned to her. “Okay, I figure you’re ticked off on a couple of levels, so I’ll pick one to start. There was no funny business going on between me and Nell. It was completely professional.”

“Son, if I thought otherwise you’d be braying like a jackass.”

“Right.” He took his glasses off, to see her more clearly, and because if she decided to try to deck him, he didn’t want them broken. “You’re angry because I brought equipment here and ran tests on Nell.”

“Bingo. I invited you here, to my home. It’s not a goddamn lab.”

“It’s also Nell’s home,” he pointed out. “I wouldn’t have brought anything if she hadn’t agreed.”

“You wheedled her.”

“I can wheedle when I have to,” he said equably. “I didn’t have to. The fact is, she was interested. She’s exploring herself, and this is part of it. I’m sorry it upsets you; I was afraid it would. And if I’d been paying more attention to the time, I’d have shut it all down before you got home.”

“So you’d have hidden it from me? That’s a nice touch.”

His own temper rumbled. “Tough to win with you, Deputy. No, I’ve never hidden my work from you, and I wouldn’t have done so now. But I’d have tried to respect your feelings about it, as I’ve tried to do from the start.”

“Then why—”

He cut her off by holding up one finger. “The simple fact is, this is my work, and you have to deal with that. But this is your home, and my being here under these circumstances upsets you. I’ll apologize for that. It’ll only take me about fifteen minutes to break this down and get it out. I’ll tell Nell I’ll take a rain check on dinner.”

“Oh, stop being such a jerk.”

“You know, Ripley, you just keep pushing and pushing until nobody wins.”

When he turned away to remove his camera from the tripod, she reached up, pulled her own hair until the sharp pain cleared her head. “Maybe I do. I didn’t ask you to leave.”

“What are you asking?”

“I don’t know! I come home after a pisser of a day, I’m tired and I’m irritable, and I walk in on you doing your mad scientist routine with Nell, who’s obviously not only cooperating but enjoying the hell out of it. I wanted a damn beer and a hot shower, not a confrontation.”

“Understandable. I can only apologize for the timing. It doesn’t change the fact that this is what I do.”

“No, it doesn’t.” Nor, she realized with a twinge, did it change the fact that she’d jumped down his throat because of it. That he’d expected her to.

Not only was she being a bitch, she was being a predictable bitch. It was lowering.

“You missed a level.”

He packed his camera, closed up his laptop. “Which is?”

“I want to know why you didn’t ask me.”

“I couldn’t ask you if you’d mind if I ran tests with Nell because you weren’t here to be asked.”

“No, why didn’t you ask me to run them with you?” As he stopped unhooking cables to stare at her, she shrugged. “I think it’s rude that you went to Nell before you came to me.”

Just when he thought he had her pegged, she changed the pattern on him. “Would you have agreed?”

“I don’t know.” She huffed out a breath. “Maybe. I’d have thought about it, anyway. But you didn’t ask.”