No response.
Ross rapped again, more sharply.
Still no answer.
Another moment's hesitation. Then, quickly, Ross slid a paper-thin variable tab into the lock-slot.
There was a click of contacts made and contacts broken. Noiselessly, the door swung back.
Swiftly, Ross stepped to one side and stood there, poised and waiting.
Nothing.
Or almost nothing.
Ross sniffed. His forehead furrowed. He stepped across the threshold; sniffed again.
Two more steps, and his foot struck something in the darkness. Stiff-fingered, he drew out his flamer; flicked it.