I didn't think much of the idea when you suggested it, but, somehow, I can't get it out of my head.

Do you still believe there was a fourth man?
If so, what was he there for ?" "That will show in time," replied Nestor, with a little pause after each word.
"But," insisted Frank, seeking to argue the matter in order to bring out the opinion of his chum, "these other men had strong motives in doing what was done there, and you don't indicate any motive the fourth man might have had!" "I have a faint hint of a motive humming in my brain," Nestor answered, "but it is not sufficiently well developed to talk about now.

There was something afoot in the building that night that has not yet come to the surface." "You surely don't believe the tales told by Scoby and Felix, or by Don Miguel, either ?" asked Frank.
"They may be telling the truth, or part of the truth.

However, Scoby and Felix are not sincere in their statements.

There is something they are not telling." "Well," Frank observed, "we ought to be getting down to brass tacks.