She was stepping into a motor-car when he came up with her.

The door closed behind her.
He seized the handle and tried to pull at it.

But a man jumped up inside and sent his fist flying into Lupin's face,
with less skill but no less force than Lupin had sent his into

Daubrecq's face.
Stunned though he was by the blow, he nevertheless had ample time to

recognize the man, in a sudden, startled vision, and also to recognize,
under his chauffeur's disguise, the man who was driving the car. It

was the Growler and the Masher, the two men in charge of the boats on
the Engbien night, two friends of Gilbert and Vaucheray: in short, two

of Lupin's own accomplices.
When he reached his rooms in the Rue Chateaubriand, Lupin, after

washing the blood from his face, sat for over an hour in a chair, as
though overwhelmed. For the first time in his life he was experiencing

the pain of treachery. For the first time his comrades in the fight
were turning against their chief.

Mechanically, to divert his thoughts, he turned to his correspondence
and tore the wrapper from an evening paper. Among the late news he

found the following paragraphs:
"THE VILLA MAXIE-THERESE CASE"

"The real identity of Vaucheray, one of the alleged
murderers of Leonard the valet, has at last been ascertained.

He is a miscreant of the worst type, a hardened criminal who
has already twice been sentenced for murder, in default, under

another name.
"No doubt, the police will end by also discovering the real name

of his accomplice, Gilbert. In any event, the examining-magistrate
is determined to commit the prisoners for trial as soon as possible.

"The public will have no reason to complain of the delays of the law."
In between other newspapers and prospectuses lay a letter.

Lupin jumped when he saw it. It was addressed:
"Monsieur de Beaumont, Michel."

"Oh," he gasped, "a letter from Gilbert!"
It contained these few words:

"Help, governor!... I am frightened. I am frightened... "
Once again, Lupin spent a night alternating between sleeplessness and

nightmares. Once again, he was tormented by atrocious and terrifying
visions.

CHAPTER IV
THE CHIEF OF THE ENEMIES

Poor boy!" murmured Lupin, when his eyes fell on Gilbert's letter next
morning. "How he must feel it!"

On the very first day when he saw him, he had taken a liking to that
well-set-up youngster, so careless, gay and fond of life. Gilbert was

devoted to him, would have accepted death at a sign from his master.
And Lupin also loved his frankness, his good humour, his simplicity, his

bright, open face.
"Gilbert," he often used to say, "you are an honest man. Do you know,

if I were you, I should chuck the business and become an honest man for
good."

"After you, governor," Gilbert would reply, with a laugh.
"Won't you, though?"

"No, governor. An honest man is a chap who works and grinds. It's a
taste which I may have had as a nipper; but they've made me lose it

since."
"Who's they?"

Gilbert was silent. He was always silent when questioned about his
early life; and all that Lupin knew was that he had been an orphan

since childhood and that he had lived all over the place, changing
his name and taking up the queerest jobs. The whole thing was a

mystery which no one had been able to fathom; and it did not look as
though the police would make much of it either.

Nor, on the other hand, did it look as though the police would consider
that mystery a reason for delaying proceedings. They would send

Vaucheray's accomplice for trial - under his name of Gilbert or any
other name - and visit him with the same inevitable punishment.

"Poor boy!" repeated Lupin. "They're persecuting him like this only
because of me. They are afraid of his escaping and they are in a hurry

to finish the business: the verdict first and then... the execution.
Oh, the butchers!... A lad of twenty, who has committed no murder, who

is not even an accomplice in the murder...
Alas, Lupin well knew that this was a thing impossible to prove and that

he must concentrate his efforts upon another point. But upon which?
Was he to abandon the trail of the crystal stopper?

He could not make up his mind to that. His one and only diversion from
the search was to go to Enghien, where the Growler and the Masher lived,

and make sure that nothing had been seen of them since the murder at the
Villa Marie-Therese. Apart from this, he applied himself to the

question of Daubrecq and nothing else.
He refused even to trouble his head about the problems set before him:

the treachery of the Growler and the Masher; their connection with the
gray-haired lady; the spying of which he himself was the object.

"Steady, Lupin," he said. "One only argues falsely in a fever. So hold
your tongue. No inferences, above all things! Nothing is more foolish

than to infer one fact from another before finding a certain
starting-point. That's where you get up a tree. Listen to your instinct.

Act according to your instinct. And as you are persuaded, outside all
argument, outside all logic, one might say, that this business turns

upon that confounded stopper, go for it boldly. Have at Daubrecq and
his bit of crystal!"

Lupin did not wait to arrive at these conclusions before settling his
actions accordingly. At the moment when he was stating them in his mind,

three days after the scene at the Vaudeville, he was sitting, dressed
like a retiredtradesman, in an old overcoat, with a muffler round his

neck, on a bench in the Avenue Victor-Hugo, at some distance from the
Square Lamartine. Victoire had his instructions to pass by that bench

at the same hour every morning.
"Yes," he repeated to himself, "the crystal stopper: everything turns on

that... Once I get hold of it... "
Victoire arrived, with her shopping-basket on her arm. He at once

noticed her extraordinaryagitation and pallor:
"What's the matter?" asked Lupin, walking beside his old nurse.

She went into a big grocer's, which was crowded with people, and,
turning to him:

"Here," she said, in a voice torn with excitement. "Here's what you've
been hunting for."

And, taking something from her basket, she gave it to him.
Lupin stood astounded: in his hand lay the crystal stopper.

"Can it be true? Can it be true?" he muttered, as though the ease of
the solution had thrown him off his balance.

But the fact remained, visible and palpable. He recognized by its shape,
by its size, by the worn gilding of its facets, recognized beyond any

possible doubt the crystal stopper which he had seen before. He even
remarked a tiny, hardly noticeable little scratch on the stem which he

remembered perfectly.
However, while the thing presented all the same characteristics, it

possessed no other that seemed out of the way. It was a crystal stopper,
that was all. There was no really special mark to distinguish it from

other stoppers. There was no sign upon it, no stamp; and, being cut
from a single piece, it contained no foreign object.

"What then?"
And Lupin received a quick insight into the depth of his mistake. What

good could the possession of that crystal stopper do him so long as he