You scouted through the basement laboratory before catching a whiff of something strange wafting out of the room ahead. You took a sharp left and found yourself in a large concrete-walled room filled with ductwork, water heaters, and a furnace. By the far wall was a hatch double door locked with two deadbolts, emblazoned with a prominent exit sign.
Sonoma was bent down in front of the duct, busying herself with an unseen burden. The screeching of a metal grate being pulled open masked the sound of your arrival. It looked like she was trying to release something into the ventilation system.
But What?