at had urged him to her rescue, her gratitude that his
daring had brought about the end she had so ardently desired. He hoped,
moreover, that there was, about her quiet manner, something to be
followed to that necessary but impulsive moment in the brown radiance of
the evil house.

Yet that illusion she did not permit him to hold for long. He left the
inspector and her at the flat with an uncomfortable feeling of having
failed to measure up to the idea of him she had developed. She did not
mention Black again, but her restraint persisted. Sooner or later, he
tried to tell himself, something would destroy that--probably another
case that would throw them together, that would make them depend one
upon the other.

At headquarters one day the doorman told him that the inspector had been
taken ill. The detective satisfied himself that nothing serious was to
be feared, so he smiled, thinking the situation might offer something
useful for himself.

It was really the trivial fact of the inspector's cold that involved
Nora and Garth in the troubles of Addington Alsop. Those gathered into
one of the most daring and dangerous cases headquarters had had since
the commencement of the period of reconstruction.

To begin with, the inspector's indisposition confined him to his flat.
It held Nora there in the part of a nurse. It drew Garth, who would
have braved the most virulent contagion to be near her. Most important
of all, it allowed the mighty Alsop to apply for police help without
fear of detection by the reporters and agents constantly swarming at
headquarters.

When Garth entered the flat that afternoon, he was, unknowingly, already
on the threshold of the strange case; for he had read in the noon
editions the brief paragraph which recited an accident to all
appearances common enough. A man had been picked up unconscious in the
middle of a quiet street. Evidently he had been struck by an automobile.
Two details, however, arrested Garth's attention. The victim, Ralph
Brown, he knew as a successful private detective. Moreover, the outrage
had occurred during the slack hours before the dawn. Apparently no clue
as to its perpetrators remained. Garth spoke of that casually to the
inspector. The huge, suffering man was scarcely intrigued. Wrapped in an
ancient dressing-gown, his throat smothered beneath flannel, he sat in
an easy chair, facing the fire, whose coals he perpetually reproved with
a frown. He groaned. There was utt