The Square Root of Murder (Professor Sophie Knowles)

was weak. I would have preferred to stand there and do arithmetic for the rest of the afternoon with the chubby, curly-haired woman.
    “I’ll walk you down.”
    Terri waddled slightly in front of me, past several bustling offices. It seemed there was a lot of paperwork to law enforcement. Old model fax machines rolled out documents and keyboards clacked.
    “Busy place,” I said, to fill in a hole in our conversation. My other option would have been to mention a new mathcast I’d seen on squaring two-digit numbers, but I didn’t want to overdo the math connection.
    Terri apologized in advance for the room I’d be waiting in. “It’s really warm in there,” she said. “I don’t know why Archie told me to put you in Interview Two, when there are better ones available with more comfortable chairs and a working A/C and all.”
    I had some idea why.
    Terri dropped me off in a dismal, stifling room with stagnant air. The furniture in Interview Two was worse than that in MAstar’s trailers, by a factor of ten. I figured they were castoffs from the government departments that had left this part of town for the right side of the tracks.
    Of the two gray metal chairs in the room, I chose the one with the least number of rips in its faux-cushioned seat. There was no clock in the room and since I tended not to wear a watch in the summer, the better to avoid a rash, I had no idea how many minutes ticked by. I alternated between letting my head hang freely from my neck onto my chest, to sitting up straight and stretching my neck backward. I paced for a while, but the room was so small the laps made me dizzy. No position was comfortable, but shifting my body around gave my muscles momentary relief.
    I tried to use the time to organize my thoughts, but there was no controlling them in this hostile environment. Images of my three students, Pam, Liz, and Casey, wearing evil masks crowded my mind and alternated with videos of Keith Appleton falling off his chair repeatedly, clutching his throat and taking his last breath each time. In the mental video, Hal and Rachel were off in a corner while Gil searched for them, a hatchet in her hand. Who said mathematicians weren’t creative?
    I wished with all my heart that Pam had let her two friends—followers, I now saw—finish their sentences. Besides that, something else nagged at me. Something one of them said at the party? On the phone the night of Keith’s murder? Probably something from the statistics seminar, like Casey’s mixing up means and medians.
    I shook my head to clear it. Bad move. A new headache set in.
    I wondered how long Archie would leave me to sweat, literally.
    The answer came when the door opened and Archie appeared. The large clock on the hallway wall behind him read five after four. I’d been ten minutes early, therefore, I’d been captive for seventy-five sweltering, mind-numbing minutes.
    “Sorry,” Archie said as he entered Interview Two looking cool and crisp, and hardly sorry. He’d probably spent the time with a cold pack around his neck.
    In spite of his name—which called to mind a bumbling, wrinkled old caricature of a detective—Archie looked like Hollywood’s idea of the insightful young cop who one-ups his dumpy-looking colleagues and his boss and takes down the serial killer. His well-groomed, sharp look, the opposite of Virgil’s, unnerved me.
    “Can I get you some coffee?” he asked.
    A hot drink. Just what I needed. I almost laughed.
    I shook my head. “No, thanks.”
    “A soda?”
    Another shake. “I’m good.”
    I kept my hands on my lap, careful not to touch anything. I pictured what Archie would do after I left, pulling out a handkerchief, picking up a soda can, and shipping it off for DNA analysis. Of course my fingerprints and DNA would be all over Keith’s office anyway, but with legitimate reasons as well as the one bad one. Still, one couldn’t be too careful.
    Archie took the seat opposite me. Although he loosened his tie, he managed to sustain the in-charge male model look.
    “So, Dr. Knowles.”
    “Sophie,” I said, eager to put this experience on an informal, less stressful level.
    “Sophie, then.” If this was Archie, yielding, I’d hate to see his rigid side. “How well did you know Dr. Appleton?”
    An easy one. I cleared my throat. “He was a colleague. We saw each other several times a week in Franklin Hall, plus there were faculty meetings, committees, the usual.”
    “Would you say you two