"At half-past six last night, sir. He was dining at his club and then
going to the New Avenue Theater. I booked a seat for him myself."

"He was going alone, then?"

"Yes."

Gatton glanced at me significantly and I experienced an uncomfortable
thrill. In the inspector's glance I had read that he suspected the
presence of a woman in the case and at the mention of the New Avenue
Theater it had instantly occurred to me that Isobel Merlin was
appearing there! Gatton turned again to Morris.

"Sir Marcus had not led you to suppose that there was any likelihood
of his _not_ returning last night?"

"No, sir; that was why, knowing his regular custom, I became so
alarmed when he failed to come back or to 'phone."

Gatton stared hard at the speaker and:

"It will be no breach of confidence on your part," he said, speaking
slowly and deliberately, "for you to answer my next question. The best
service you can do your late master now will be to help us to
apprehend his murderer."

He paused a moment, then:

"Was Sir Marcus interested in some one engaged at the New Avenue