you have done before. But
why in this case particularly?"

"It's a case altogether out of the ordinary, and one of a string of
such, all of which you have at your fingers' ends. And I don't mind
confessing that this man Mayes is a little too big a handful for
one--for me, at any rate. I wish you could work with me over this; in
fact, in the special circumstances I've a good mind to ask to have you
retained, as an exceptional measure. But the thing's urgent, and there's
red-tape!"

Hewitt had taken a glance at his desk tablet, which he now flung down.

"I'll do it for love," he said, "if necessary. My appointment list is
uncommonly slack just now, and even if it weren't, I'd make a
considerable sacrifice rather than be out of this. This fellow Mayes is
a dangerous man; and I feel it a point of honour that he shall not
continue to escape. Moreover, I have begun to form a certain theory as
to the Red Triangle, and all there is at the back of it--a theory I
would rather keep to myself till I see a little more, since as it stands
it may only strike you as fantastic, and if it is wrong it may lead some
of us off the track; but it is a theory I wish to test to the end. So
I'm with you, Plummer, if you'll allow it; and you can make your
official application for a special retainer or not, just as you please."

Plummer was plainly delighted.

"Most certainly I will," he said. "Shall I give you the heads of the
case, or will you come to the Admiralty and see for yourself?"

"Both, I think," said Hewitt. "But first I will send a telegram to
Peytral. Then you can give me the heads of the case as we go along, and
I will look at the place for myself. I am in this case heart and soul,
pay or no pay--and I expect my friend Brett would like to be in it, too.
Is there any objection?"

"Well," Plummer answered, a little doubtfully, "we're glad of outside
help, of course, but I'm not sure, officially----"

"Of course you are always glad of outside help," Hewitt interrupted,
"and in this case we may possibly find Brett more useful than you think.
Consider now. He has seen a good deal of these cases--quite as much as
you, in fact--but he is the only one of the three of us whom Mayes does
not know by sight. Remember, Mayes saw us both in the affair of Mr.
Jacob Mason, and he saw you again in the case of the Lever Key--escaped,
in fact, because he instantly recognised you. I'll answer for Brett's
discretion, and I'm sure he'll be glad