Mainline by Deborah Christian

potential. He knew it was part fact and part illusion, and he needed to get moving before the dose wore off. He opened the crawler's door and climbed out into the blustering storm.
    The agent walked away from the vehicle, into the snow-laden darkness beyond a feebly glowing lightpost. Better there than toward the longhouse gate, where security cameras might pick up his disappearing act. As soon as he was in relative obscurity he stood motionless and gathered his concentration. When the next flurry of snow whipped over him, Vask closed his eyes against the sting of icy flakes. He stood stolid and relaxed, then let himself go into the trance required for sideslipping.
    Soon a peculiar, skin-crawling sensation came over him as his molecular structure unphased. Like many psi powers, phase-shifting was simply a matter of manipulating the body's natural energy field. Or, not "simply." It was a difficult skill to master, and few could learn to do it.
    But Vask had. Every particle, every elemental chain that composed the man on the physical plane shifted its vibratory frequency ever so slightly up-spectrum. He was there, yet not there, existing in a state more akin to light than gross physical matter. Straddling dimensions, the entity that was Vask became a semi-coherent form, one no longer hindered by the physical stuff of his natural state. A form no longer visible to earthly sight at all.
    The snowstorm faded to a cloud of gray mist as Vask phased out of the realm of ordinary sensation. He no longer felt cold or stinging ice. His clothing, caught within the radius of his body's natural bio-electric field, traveled with him, although it, too, lacked substance and tangible presence.
    He walked in a foggy half-world where mist-soft objects glowed with a blue-gray luminescence born of radiant molecular energy. He approached the shadowy gate of Tyree Longhouse and moved through the incorporeal structure of the bars. As he pushed through, he felt a crawling sensation in the path of the earthly material. It was not a horrific feeling; neither was it pleasant. He gathered his nerve before pushing through the door of the long-house in the same manner.
    What seemed to be rough wood planking was a veneer over thick steel, with a reinforced core like a blast door. The crawling sensation came again, throughout his body. Vask closed his eyes, hating the disorientation of walking through what his mind told him should be—no, was— a solid object. Only when the sensation was gone and he was on the other side did he open his eyes.
    At the far end of the great hall, Lish and Reva sat beside the firepit drinking wine. Vask could hear nothing of their conversation, for sound, like other physical sensations, was not perceivable in a phase-shifted state. To eavesdrop, he would have to sideslip back to the material plane, then either hide in a mundane manner or use his blindspot ability to avoid detection. Blindspot-ting would exhaust even more of his powers; it would be better to simply hide.
    The furnishings in the room were sparse: cushions and mats, a few benches and tables along the walls, and the sideboard that held the dinner dishes. That high-backed furnishing stood behind Lish.
    Vask wafted through pillows and cushions, skirting the women as he came closer to them. Moving through the inanimate was uncomfortable enough; sideslipping through living creatures was even more disturbing, and could be detected by the highly sensitive, at least as a chill or sense of presence. He took care to avoid the women as he moved past toward the sideboard.
    The furniture was angled so that he would be hidden from sight behind it. The shadows there were deep. He would not be able to watch his subjects from that vantage, though he could listen to their conversation, and he could blindspot if either walked around the room.
    He moved to the space behind the sideboard, assumed what would be a comfortable sitting position, and shifted the phase of his structure back