Mr. Briggerland, killing time on the quay at Monaco, saw the Jungle Queen come into harbour and watched Marcus land, carrying his lines in his hand.

As Marcus came abreast of him he called and Mr. Stepney looked round with a start.

"Hello, Briggerland," he said, swallowing something.

"Well, have you been fishing?" asked Mr. Briggerland in his most paternal manner.

"Yes," admitted Marcus.

"Did you catch anything?"

Stepney nodded.

"Only one," he said.

"Hard luck," said Mr. Briggerland, with a smile, "but where is Mrs. Meredith—I understood she was going out with you to-day?"

"She went to San Remo," said Stepney shortly, and the other nodded.

"To be sure," he said. "I had forgotten that."

Later he bought a copy of the Nicoise and learnt of the tragedy on the San Remo road. It brought him back to the house, a visibly agitated man.

"This is shocking news, my dear," he panted into the saloon and stood stock still at the sight of Mr. Jack Glover.

"Come in, Briggerland," said Jack, without ceremony. There was a man with him, a tall, keen Frenchman whom Briggerland recognised as the chief detective of the PrÉfecture. "We want you to give an account of your actions."

"My actions?" said Mr. Briggerland indignantly. "Do you associate me with this dreadful tragedy? A tragedy," he said, "which has stricken me almost dumb with horror and remorse. Why did I ever allow that villain even to speak to poor Lydia?"

"Nevertheless, m'sieur," said the tall man quietly, "you must tell us where you have been."

"That is easily explained. I went to San Remo."

"By road?"

"Yes, by road," said Mr. Briggerland, "on my motor-bicycle."

"What time did you arrive in San Remo?"

"At midday, or it may have been a quarter of an hour before."

"You know that the murder must have been committed at half-past eleven?" said Jack.

"So the newspapers tell me."

"Where did you go in San Remo?" asked the detective.

"I went to a cafÉ and had a glass of wine, then I strolled about the town and lunched at the Victoria. I caught the one o'clock train to Monte Carlo."

"Did you hear nothing of the murder?"

"Not a word," said Mr. Briggerland, "not a word."

"Did you see the car?"

Mr. Briggerland shook his head.

"I left some time before poor Lydia," he said softly.

"Did you know of any attachment between the chauffeur and your guest?"

"I had no idea such a thing existed. If I had," said Mr. Briggerland virtuously, "I should have taken immediate steps to have brought poor Lydia to her senses."

"Your daughter says that they were frequently together. Did you notice this?"

"Yes, I did notice it, but my daughter and I are very democratic. We have made a friend of Mordon and I suppose what would have seemed familiar to you, would pass unnoticed with us. Yes, I certainly do remember my poor friend and Mordon walking together in the garden."

"Is this yours?" The detective took from behind a curtain an old British rifle.

"Yes, that is mine," admitted Briggerland without a moment's hesitation. "It is one I bought in Amiens, a souvenir of our gallant soldiers——"

"I know, I quite understand your patriotic motive in purchasing it," said the detective dryly, "but will you tell us how this passed from your possession."

"I haven't the slightest notion," said Mr. Briggerland in surprise. "I had no idea it was lost—I'd lost sight of it for some weeks. Can it be that Mordon—but no, I must not think so evilly of him."

"What were you going to suggest?" asked Jack. "That Mordon fired at Mrs. Meredith when she was on the swimming raft? If you are, I can save you the trouble of telling that lie. It was you who fired, and it was I who knocked you out."

Mr. Briggerland's face was a study.

"I can't understand why you make such a wild and unfounded charge," he said gently. "Perhaps, my dear, you could elucidate this mystery."

Jean had not spoken since he entered. She sat bolt upright on a chair, her hands folded in her lap, her sad eyes fixed now upon Jack, now upon the detective. She shook her head.

"I know nothing about the rifle, and did not even know you possessed one," she said. "But please answer all their questions, father. I am as anxious as you are to get to the bottom of this dreadful tragedy. Have you told my father about the letters which were discovered?"

The detective shook his head.

"I have not seen your father until he arrived this moment," he said.

"Letters?" Mr. Briggerland looked at his daughter. "Did poor Lydia leave a letter?"

She nodded.

"I think Mr. Glover will tell you, father," she said. "Poor Lydia had an attachment for Mordon. It is very clear what happened. They went out to-day, never intending to return——"

"Mrs. Meredith had no intention of going to the Lovers' Chair until you suggested the trip to her," said Jack quietly. "Mrs. Cole-Mortimer is very emphatic on that point."

"Has the body been found?" asked Mr. Briggerland.

"Nothing has been found but the chauffeur," said the detective.

After a few more questions he took Jack outside.

"It looks very much to me as though it were one of those crimes of passion which are so frequent in this country," he said. "Mordon was a Frenchman and I have been able to identify him by tattoo marks on his arm, as a man who has been in the hands of the police many times."

"You think there is no hope?"

The detective shrugged his shoulders.

"We are dragging the pool. There is very deep water under the rock, but the chances are that the body has been washed out to sea. There is clearly no evidence against these people, except yours. The letters might, of course, have been forged, but you say you are certain that the writing is Mrs. Meredith's."

Jack nodded.

They were walking down the road towards the officers' waiting car, when Jack asked:

"May I see that letter again?"

The detective took it from his pocket book and Jack stopped and scanned it.

"Yes, it is her writing," he said and then uttered an exclamation.

"Do you see that?"

He pointed eagerly to two little marks before the words "Dear friend."

"Quotation marks," said the detective, puzzled. "Why did she write that?"

"I've got it," said Jack. "The story! Mademoiselle Briggerland told me she was writing a story, and I remember she said she had writer's cramp. Suppose she dictated a portion of the story to Mrs. Meredith, and suppose in that story there occurred this letter: Lydia would have put the quotation marks mechanically."

The detective took the letter from his hand.

"It is possible," he said. "The writing is very even—it shows no sign of agitation, and of course the character's initials might be 'L.M.' It is an ingenious hypothesis, and not wholly improbable, but if this were a part of the story, there would be other sheets. Would you like me to search the house?"

Jack shook his head.

"She's much too clever to have them in the house," he said. "More likely she's put them in the fire."

"What fire?" asked the detective dryly. "These houses have no fires, they're central heated—unless she went to the kitchen."

"Which she wouldn't do," said Jack thoughtfully. "No, she'd burn them in the garden."

The detective nodded, and they returned to the house.

Jean, deep in conversation with her father, saw them reappear, and watched them as they walked slowly across the lawn toward the trees, their eyes fixed on the ground.

"What are they looking for?" she asked with a frown.

"I'll go and see," said Briggerland, but she caught his arm.

"Do you think they'll tell you?" she asked sarcastically.

She ran up to her own room and watched them from behind a curtain. Presently they passed out of sight to the other side of the house, and she went into Lydia's room and overlooked them from there. Suddenly she saw the detective stoop and pick up something from the ground, and her teeth set.

"The burnt story," she said. "I never dreamt they'd look for that."

It was only a scrap they found, but it was in Lydia's writing, and the pencil mark was clearly visible on the charred ashes.

"'Laura Martin,'" read the detective. "'L. M.,' and there are the words 'tragic' and 'remorse'."

From the remainder of the charred fragments they collected nothing of importance. Jean watched them disappear along the avenue, and went down to her father.

"I had a fright," she said.

"You look as if you've still got it," he said. He eyed her keenly.

She shook her head.

"Father, you must understand that this adventure may end disastrously. There are ninety-nine chances against the truth being known, but it is the extra chance that is worrying me. We ought to have settled Lydia more quietly, more naturally. There was too much melodrama and shooting, but I don't see how we could have done anything else—Mordon was very tiresome."

"Where did Glover come from?" asked Mr. Briggerland.

"He's been here all the time," said the girl.

"What?"

She nodded.

"He was old Jaggs. I had an idea he was, but I was certain when I remembered that he had stayed at Lydia's flat."

He put down his tea cup and wiped his lips with a silk handkerchief.

"I wish this business was over," he said fretfully. "It looks as if we shall have trouble."

"Of course we shall," she said coldly. "You didn't expect to get a fortune of six hundred thousand pounds without trouble, did you? I dare say we shall be suspected. But it takes a lot of suspicion to worry me. We'll be in calm water soon, for the rest of our lives."

"I hope so," he said without any great conviction.

Mrs. Cole-Mortimer was prostrate and in bed, and Jean had no patience to see her.

She herself ordered the dinner, and they had finished when a visitor in the shape of Mr. Marcus Stepney came in.

It was unusual of Marcus to appear at the dinner hour, except in evening dress, and she remarked the fact wonderingly.

"Can I have a word with you, Jean?" he asked.

"What is it, what is it?" asked Mr. Briggerland testily. "Haven't we had enough mysteries?"

Marcus eyed him without favour.

"We'll have another one, if you don't mind," he said unpleasantly, and the girl, whose every sense was alert, picked up a wrap and walked into the garden, with Marcus following on her heels.

Ten minutes passed and they did not return, a quarter of an hour went by, and Mr. Briggerland grew uneasy. He got up from his chair, put down his book, and was half-way across the room when the door opened and Jack Glover came in, followed by the detective.

It was the Frenchman who spoke.

"M'sieur Briggerland, I have a warrant from the PrÉfect of the Alpes Maritimes for your arrest."

"My arrest?" spluttered the dark man, his teeth chattering. "What—what is the charge?"

"The wilful murder of FranÇois Mordon," said the officer.

"You lie—you lie," screamed Briggerland. "I have no knowledge of any——" his words sank into a throaty gurgle, and he stared past the detective. Lydia Meredith was standing in the doorway.