"Did you know when I came aboard?"

She nodded and said, "I was out on deck, getting some fresh air. It was foggy, so I didn't stay long. I was there by the rail near the bow when you came aboard."

"Did you see anyone else whom you knew aboard the ship?"

"No."

"You'd swear to that?"

"Why, yes, if I had to." She settled back in her chair and said, "Now if you've quite finished, you might go to the bar and get me a Tom Collins. I can't satisfy my craving for tobacco by puffing at these insipid cigarettes. I'm dying for a real smoke. To tell you the truth, I went up on deck to find a place where I could puff on a cigar, but there was an amorous couple huddled against the rail and I was afraid the young man would go into a monastery and shave his head if I shattered his romantic ideals by letting him see what age and freedom will do for a woman."

Mason leaned across the table, studied the twinkling humor of the alert gray eyes and said abruptly, "Sam Grieb's been murdered."

Her face was an expressionless mask. "How do you know?" she asked.

Mason said slowly, "You knew he'd been murdered."

"I didn't know any such thing."

"Then why did you lie to me?"

The gray eyes glinted dangerously. "I'm not accustomed," she said, "to being talked to…"

"Why did you lie to me?" Mason asked.

"What do you mean?"

"You lied to me about Sylvia."

"What about her?"

"She was aboard, and you knew she was aboard. You saw her here."

The gray eyes faltered. She stretched a jeweled hand across the table and said, "Give me one of your cigarettes."

Mason opened his cigarette case. She took a cigarette, Mason scraped a match on the underside of the table, held the flame to her cigarette, took another cigarette for himself, lit it, and exhaled twin streams of white smoke through appreciative nostrils.

"I'm listening," he told her.

She avoided his eyes, puffed rapidly at the cigarette, took it from her lips, ground it into the ash tray and said, "Isn't there some place where we can smoke?"

"It may not be a good idea for us to be together at all," Mason said. "Right now this is the best place for us to talk. The gang's up at the bar with their backs turned to us… and I'm still listening."

She toyed with the rim of the ash tray with nervous fingers, then looked up at him and said, "Yes, Sylvia was out here."

"I know she was out here. Why didn't you tell me she was here?"

"Because… Well, because of lots of things."

"What, for instance?"

"The way Sylvia acted."

"For God's sake," Mason told her impatiently, "quit beating around the bush. I'm a lawyer retained by you to protect Sylvia's interests. How the devil can I do it if you keep playing button-button-who's-got-the-button? Inside of a few minutes the officers are going to show up, and the party may get rough. I want to know what happened, what I've got to guard against, and what I've got to meet."

She said slowly, "Sylvia went to the offices. I was afraid she was going to play right into Grieb's hand, and I didn't know what to do. I didn't want her to see me. That was why I went out on deck. I kept hoping you'd turn up. Sure enough, you came pretty soon after that. I heaved a big sigh of relief. I thought you'd probably run into Sylvia in the office."

"Now wait a minute," Mason said, "let's get this straight. Sylvia came aboard before I did?"

"Yes."

"How many boats before?"

"I don't know. I didn't see her when she first came aboard. Naturally, I hadn't expected she would come here at all. Otherwise I'd have stayed away. I didn't want her to know I was taking an interest in her affairs. If she'd seen me, she'd have known at once…"

"Never mind that," Mason said. "Let's get down to brass tacks and stay there. Where was she when you first saw her?"

"She was just coming into the casino."

"What did you do?"

"I kept out of sight. She went to a table, said something to the croupier, and then headed straight for that corridor which goes into Grieb's office… I slipped up the stairs and went out on deck."

"Was she betting?"

"No, she was asking something of the man at the wheel. I thought perhaps she was asking whether Grieb was in."

"So what?" Mason asked.

"Well, that's all. I went up on deck and stayed there. It was foggy and I got chilled, but I didn't dare go back for fear I'd run into her."

"Now, where was her husband?"

"Frank Oxman," she said, "must have come aboard earlier, perhaps while I was in the casino. The first I knew that he was aboard was when I saw him leave. He came out of the salon wearing a cap and overcoat, walked within a very few feet of me, and I was afraid he'd see me. Then he went to the place where passengers wait, and went down the stairs and took the boat which pulled out just a few minutes after you'd come aboard."

"Was anyone following him?" Mason asked.

She shook her head and said, "I don't think so," then said, "Wait a minute. There was a man who had been wandering around as though he was looking for someone. He kept hanging around but didn't gamble. He went back on the same speed boat Frank took. He may have been a detective."

"And I had arrived on board before that?"

"Yes. But not very long before. He left perhaps ten minutes after you arrived. You may have met him."

Mason frowned thoughtfully, then said, "I wouldn't have known him if I had met him. What about Sylvia?"

"I stayed out on deck. I didn't want Sylvia to see me. I must have been there ten or fifteen minutes when Sylvia came out. A man followed her. He said, 'Frank's aboard. Beat it,' and then he stepped back into the casino. Sylvia went…" She abruptly stopped in mid-sentence.

"Go on," Mason said, "went where?"

She kept her jeweled fingers busy with the edge of the cigarette tray and said, "Went back."

"Back where?"

"Back on the speed boat, of course."

Mason studied her face. "That wasn't what you were going to say."

"Yes, it was."

Mason said, "Don't be a fool. I know you started to say something else."

"Why?"

"Because the way you bit off that sentence showed that you'd almost betrayed yourself into saying something you didn't want to say. Then when I asked you where she went and you said that she went back to the shore, there was relief in your voice to think you hadn't gone far enough with your other sentence to keep from patching it up. Now I want to know where Sylvia went when she came out of the casino."

Matilda Benson lit another cigarette and puffed on it.

"Tell me where she went," Mason demanded insistently.

"She went to the rail."

"And what did she do at the rail?"

Matilda Benson said slowly, "She fumbled with her handbag, and a second or so later I heard something splash in the water."

"Something heavy?"

"It made a splash."

"Was it a gun?"

"I'm sure I couldn't tell you what it was."

"Did anyone else see her?"

Matilda Benson delayed the shake of her head for almost a second.

Mason said, "In other words, someone did see her."

"The young couple who were doing the necking may have seen her. I don't know. It depends upon how engrossed they were in what they were doing. You see, when Sylvia came out of the lighted interior her eyes were unaccustomed to the darkness and she stood quite close to the young couple, apparently without knowing it. Just before the sound of the splash, the neckers acted as though they'd seen something, and I heard them whisper excitedly. Then Sylvia ran down to the speed boat."

"Sylvia was standing close to you?"

"Quite close, yes."

"Now wait a minute," Mason went on. "There was a speed boat waiting at the landing?"

"Yes."

"Couldn't the people in that launch have seen her toss something overboard?"