One advantage to Mackenzie's power was that it was hard to sneak up on her when outside in an urban environment. Most forms of pavement had silica in it, and if someone was touching it and within a certain proximity to Mackenzie, she knew their approximate location and that it was a person she was dealing with. She wasn't able to distinguish between individuals that way, though. It served more as a radar.
It was a good thing she had this ability, because tonight, she was overworked, tired, and stressed. She was working on several cases, and she had a sneaking suspicion that people were pushing her cases ahead on purpose - to make her screw up. As far as Mackenzie was concerned, those same people could sit and rotate on a cactus. She was an achiever, and would find ways to make things happen the way she wanted them to.
"Ever heard of phoning to schedule an appointment?" she replied, taking a calming drag from her cigarette. "It's generally the polite thing to do. But since you've been outside my office for hours, and it's not exactly warm out, sure. We can have a discussion."