Inch by inch she opened the door more widely, took one step forward, and checked herself.

A sound, just audible at the far end of the conservatory, had caught her ear.
She listened--satisfied herself that she was not mistaken--and drawing back with a frown of displeasure, softly closed the door again, so as to hide herself from view.

The sound that had disturbed her was the distant murmur of men's voices (apparently two in number) talking together in lowered tones, at the garden entrance to the conservatory.
Who were the men?
and what would they do next?
They might do one of two things: they might enter the drawing-room, or they might withdraw again by way of the garden.

Kneeling behind the door, with her ear at the key-hole, Grace Roseberry waited the event..