After the doors were shut, the two robots unfolded into humanoid shapes and the four of them walked down into the darkness, lighting the way with bike headlights and hand-held flashlights.

“So what are we doing down here, anyway?” Lisa asked after a while. “After all, since they don’t have what Sera knows, their plans are blocked, right?”

“There are a few others who know these tunnels almost as well as I do,” Sera said. “They could have snagged some of them as a backup. I would have.”

“So we’re checking for stuff that’s out of place,” James said. “Recent construction, or stuff that just plain shouldn’t be here.”

Sera held up a hand for silence, dimmed her lights, and stepped ahead to a T-junction. “Footsteps,” she reported in a whisper.

“Security?” Lisa whispered.

“They don’t come down here,” James said. “It’s either other VADders or…someone else.”

“Either way, it’s trouble,” Sera hissed. “Or at least, we might have some explaining to do.”

Lisa hefted her TASER. “Or they might. Get ready, people.”