The device is real.

You've inspected enough buildings to know what a boiler looks like, and this isn't one. It's wedged behind the utility rack in sub-basement 2 — a metal box with a cell phone taped to its face, wires threading into something you don't want to think about.

You called it in forty seconds ago. Bomb squad is seventeen minutes out. The police dispatcher told you to leave the building.

But it's 2:15 on a Tuesday. The directory in the lobby listed nine active tenants across twelve floors. You passed a daycare sign on the third floor on your way in.

Seventeen minutes. The stairwell door is right there.