"Thanks a lot," Mason said. "I'll think it over."

  As Della Street held the corridor door open for Montrose Foster, he twisted his head with a quick, terrierlike motion, wreathed his face into a smile and hurried out into the corridor.

  The door slowly closed behind him and Della Street turned to Mason.

  "The plot thickens," she said.

  "The plot," Mason said, frowning thoughtfully, "develops lumps similar to what my friend, on a camping trip, called Thousand Island gravy."

  "Well?" she asked.

  "Let's start taking stock of the situation," he said. "Foster was the brains behind a lost heirs organization. He dug out the cases and carried the financial burden. Boring, with his impressive manner and his dignified approach, was the contact man.

  "Now then, if any unusual case had been uncovered, if any information had been turned up, one would think Foster would have been the man to do it, not Boring."

  "I see your point," Della Street said.

  "Yet Boring is the one who turns up the case and despite the fact that Foster had been directing his activities, Foster doesn't have a single lead as to what the case is. So now Foster is desperately trying to find out who the heir is and start backtracking from that angle."

  "Well," Della Street said, "it's a tribute to your thinking that you figured it out this far, largely from studying the contract."

  "I'm not handing myself any bouquets," Mason said. "I should have figured it out sooner… Now then, Foster is evidently having Boring shadowed."

  "Otherwise he wouldn't have known he came here?"

  Mason nodded.

  "And we're having Boring shadowed," Della Street said.

  "Shadows on shadows," Mason told her. "Come on, Della, we're going to have dinner on the office expense account and think things over. Then I'll drive you home."

  "Cocktails?" Della Street asked, with a smile.

  "The works," Mason said. "Somehow I feel like celebrating. I love to get into a situation where everyone is trying to double-cross everyone else."

  "What about Dianne? Do we talk with her and tell her what we have discovered?"

  "Not yet," Mason said. "We do a little thinking first; in tact, we do a lot of thinking."

  CHAPTER SIX

  A routine court hearing on Tuesday morning developed into a legal battle which ran over into the afternoon and it was three-thirty that afternoon before Mason checked in at his office.

  "Hello, Della," the lawyer said. "What's new?"

  "Mostly routine," she said. "How did the court hearing go?"

  Mason grinned. "Things were looking pretty black and then the attorney on the other side started arguing with the judge over a minor point and the argument progressed to a point where there was considerable heat on both sides. By the time the hearing was finished the judge decided it our way."

  "And what did you do?" she asked, with exaggerated innocence. "I suppose you just stood there with your hands in your pockets while the attorney and the judge were arguing."

  "I tried to act the part of a peacemaker," Mason said. "I poured oil on the troubled flames."

  Della Street laughed. "I'll bet you did just that."

  "What's new with our case involving the curvaceous blonde, Della?"

  "There seems to be a lot of activity centering in Riverside," she said. "Paul Drake reports that Harrison Boring has gone to Riverside. He is now registered in the Restawhile Motel and is in Unit 10.

  "Drake's man also reports that Boring is being shadowed by another agency."

  "You mean he's wearing two tails and doesn't know about either one?" Mason asked.

  "Apparently not," Della Street said. "Of course, under the circumstances Drake's man is being most discreet and is relying as much as possible on electronic shadowing devices which send out audible signals to the car following. He thinks the other agency is using contact observation with no electronic shadowing. So far, Boring apparently isn't suspicious. Paul says the man is hurrying around, covering a lot of territory."

  Mason settled back in his swivel chair. "Hurrying around, eh?" he said musingly.

  "Here's the mail," Della Street said, sliding a stack of letters across Mason's desk.

  Mason picked up the top letter, started to read it, put it down, then pushed the pile of mail to one side, sat for more than a minute in thoughtful silence.

  "Something?" Della Street asked.

  "I'm toying with an idea," Mason said, "and hang it, the more I think of it, the more plausible it seems."

  "Want to talk it out or let it incubate?" she asked.

  "I think I'd like to talk it out," Mason said, "and let's see if it isn't logical. Boring was working on lost heirs, obscure estates. Yet when Foster tried to backtrack his activities, he couldn't find anything. Nevertheless, Foster is a pretty thoroughgoing chap and he has the inside track. In the first place, he knows all the routine methods of investigation and in the second place he knew exactly where Boring had been and what activities he had engaged in. Yet nothing that he has been able to uncover gives any clue to what triggered Boring's break with him."

  Della Street, knowing that Mason was simply thinking out loud, sat thoughtfully attentive, furnishing him with a silent audience.

  "So suddenly Harrison T. Boring comes to Dianne Alder," Mason said, "and ties her up on a contract, but the contract is so disguised that neither she nor anyone else who might look at the contract would tumble to the fact that it was a lost heir's contract; the sugar-coating disguised the pill to such an extent that the whole thing looked like a piece of candy."

  Della Street merely nodded.

  "Now then," Mason went on, "Montrose Foster. Regardless of the fact that he's a little terrier, but no one's dummy, he begins to think that perhaps he should start working on the case from the other end and is anxious to find out who Boring has been seeing."

  Again Della Street nodded.

  "He is having Boring shadowed. He undoubtedly knows that Boring is seeing Winlock. But Winlock doesn't seem to be the solution to the problem, at least as far as Foster is concerned.

  "Now, that's where we're one step ahead of Montrose Foster. We know that whatever lead Harrison Boring may have uncovered, he followed it to Dianne Alder. Dianne Alder is the target in the case, the pot of gold at the end of the rainbow."

  Mason was silent for a few seconds, then he said, "Yet, having found Dianne Alder and having tied her up, Boring suddenly lets her go.

  "Now, why?"

  Della Street merely sat looking at him, making no comment.

  "The reason is, of course," Mason said, "that the advantage Boring intended to get from his contract with Dianne-and that must have been a considerable advantage for him to put out a hundred dollars a week-has been superseded by something much more profitable to Harrison Boring."

  "Such as what?" Della Street asked.

  "Blackmail."

  "Blackmail!" she exclaimed.

  "That's right," Mason said. "He started out on a missing heir's contract and he suddenly shifted to blackmail. That is about the only explanation that would account for his going to all that trouble to sign Dianne up on a missing heir's contract and then suddenly drop her."

  "But why would blackmail tie in with missing heirs?" she asked.

  "Because," Mason said, "we've been looking at the whole picture backwards. There aren't any missing heirs."

  "But I thought you just said Dianne was a missing heir."

  "We may have started in with that idea," Mason said, "but it's a false premise and that's why we aren't getting anywhere, and that's why Montrose Foster isn't getting anywhere. Dianne Alder isn't a missing heir; this is a case of a missing testator."

  "What do you mean?"

  "Dianne's father was killed some fourteen years ago, drowned accidentally while boating in the channel, but his body was never found."

  "Then, you mean…?"

  "I mean," Mason said, "that his body wasn't found because he wasn't dead. He was rescued in some way and decided to leave the impression that he was dead. He went out and began life all over and probably amassed something of a fortune.

  "He probably was tired of his home life, wanted to disappear the way many men do, but never had the opportunity until that boating accident."

  "So then?" Della Street asked, with sudden excitement.

  "So then," Mason said, "we start looking for a wealthy man-someone who has no background beyond fourteen years ago, someone who couldn't divorce his wife because he was supposed to be dead, someone who has since remarried, someone who is exceedingly vulnerable, therefore, to blackmail.

  "Dianne, as his daughter, would have a claim which could be enforced."

  "But didn't Dianne's mother take all of the estate?" Della Street asked.

  "All that she knew about," Mason said. "All the estate that Dianne's father left at the time of his disappearance. But technically he was still married to Dianne's mother. Technically anything that he acquired after his disappearance and before the death of Dianne's mother was community property."

  "Then," Della Street said, with sudden excitement, "the key to the whole thing is George D. Winlock."

  "Exactly," Mason said. "Winlock, the wealthy man whom Harrison Boring is cultivating at the moment; Winlock, the real estate speculator who showed up in Riverside about fourteen years ago as a salesman, who started plunging in real estate, became wealthy, and is now one of the town's leading citizens; Winlock, who has a high social position, a wife who really isn't a wife… No wonder Boring was willing to let Dianne off the hook! He had landed a bigger fish."

  "I take it," Della Street said, "that we go to Riverside."

  Mason grinned. "Get your things packed, Della. Put in some notebooks and pencils. We go to Riverside."

  "And we see George D. Winlock?"

  "We make some very careful investigations," Mason said, "and we are very, very careful indeed not to upset any apple carts, not to make any accusations, not to jump to any false conclusions, but very definitely we see George D. Winlock."

  "And when we see him?"

  "We see him as Dianne Alder's attorney, and the minute we do that I think you will find that Harrison T. Boring's blackmail has been dried up at the source. And, since Boring has repudiated his contract with Dianne, whatever we can get for her by way of a settlement will be pure velvet to her.

  "How long will it take you to get some things packed, Della?"

  She smiled. "Five minutes. I've been through this same thing so often that I'm now keeping an overnight bag in the coat closet."

  CHAPTER SEVEN

  Sid Nye, Paul Drake's right-hand man, was waiting for Perry Mason when he and Della Street arrived at the colorful Mission Inn Hotel in Riverside.

  "Hello, Sid," Mason said, shaking hands. "You know Della Street. What's new?"

  "Something I want to talk over with you," Nye said. "I talked with Paul on the phone and he said you were on your way up here and should be here any minute."

  Della Street filled out the registration cards, and Mason, Nye and Della were shown up to the lawyer's suite. Mason ordered a round of drinks, and Nye, settling himself comfortably in the chair, said, "The fat seems to be in the fire."

  "Just what happened?" Mason asked.

  "I don't know all of the ramifications of the case," Nye said, "but it seems that you were having a Harrison T. Boring shadowed."

  "That's right. What happened?"

  "Apparently he got wise that he was being tailed, but it wasn't our fault. There was another man following him, and Boring first became suspicious because the other man was using contact shadowing."

  "Go ahead," Mason said.

  "You remember Moose Dillard?" Nye asked.

  Mason frowned, then said, "Oh, yes. I place him now. The big fellow that I represented when he was in a jam over losing his license."

  "That's right. That was when he lost his temper and flattened a politician who was calling him names. Personally I think the politician had it coming to him, but that's neither here nor there. The guy had political influence and Dillard has a hell of a temper. Anyway, Moose Dillard was tailing Boring. He put an electronic bug on Boring's car so the tailing could be done without giving Boring any cause for alarm, and there's no reason on earth Boring should have known he was being shadowed if it hadn't been for this other man using contact methods.

  "Well, Boring spotted the other shadow and started out to ditch him, and did a good job of it. That other shadow was left way back in Hollywood somewhere, but it made Boring shadow conscious.

  "Of course, with our electronic tailing devices, Moose Dillard had no trouble. Anyhow, when a guy once gets suspicious, Dillard is such a big guy it's hard to forget him. A tail should be an inconspicuous fellow who can mingle with the crowd, and Dillard has always had a little trouble fading out because of his build, but he's the best automobile tail in the business. He's a genius at handling a car. He wraps those big hands of his around the steering wheel and the car seems to be a part of him."

  Mason nodded. "What happened?"

  "Well, Boring decided to come back to Riverside. I don't know what it was, probably a telephone conversation he had with someone. Anyway, he was in Hollywood, then he threw a suitcase into his car and started out at high speed. He cut figure eights and lost the other shadow. Dillard kept on his tail. After they hit the freeway, Dillard kept pretty well in the background, relying on the electronic device to keep him posted."

  "And what happened?"

  "Boring went to Winlock's office, then to the Restawhile Motel here and registered in Unit io. Dillard waited awhile, then registered and got Unit Number 5, which is across the way from Unit io and would give a pretty good view of Boring's place.

  "Now, here's the peculiar thing: Dillard checked in and drew the curtains across the window but left just a little crack in the curtain so he could see out, and after a while he saw Boring come out, cross over directly to Dillard's automobile, open the door and start prowling around."

  "What did Dillard do?"

  "He sat tight. He said he was inclined to go out and grab the guy by the collar and give him a good shaking but he remembered the trouble he'd been in before, so he just sat in there and took it."

  "What was Boring looking for?"

  "Presumably he was suspicious of Dillard and wanted to find out something about the registration of the automobile."

  "Did he learn anything?"

  "That's anybody's guess. The registration is in the name of Paul Drake as an individual and, of course, in order to comply with California law there's a certificate of registration in a cellophane window strapped to the steering post."

  "So Dillard sat tight?"

  "Dillard sat tight but he's afraid he's been spotted and he wants instructions."

  Mason thought for a minute, then said, "Tell him to stay right there in the unit and keep his eye on the unit where Boring is staying. I want to know everyone who comes to see Boring and I want to know what time Boring goes out."

  "But suppose Boring does go out. Does Dillard try to shadow him?"

  "No," Mason said. "It would be too dangerous under the circumstances. He'd be spotted even if he was using an electronic shadowing device. He'll just have to sit tight."

  "The guy hasn't had any dinner," Nye said. "He's a big guy and he gets hungry."

  "Well, I don't want to take a chance on letting him go out, at any rate while Boring is there. Do you folks have a good woman operative up here?"

  "Not up here but we could probably get one. What do you want?"

  "A good-looking woman could go into Dillard's apartment looking as though she were some married woman on a surreptitious date and probably smuggle Dillard in something to eat. It wouldn't be what he wants, but she could get some hamburgers and a Thermos jug of coffee and carry them in. Then if Boring is turning the tables on Dillard and keeping an eye on Dillard's apartment, the fact that this woman goes in there with just the right furtive attitude will probably reassure Boring and, at the same time, give Dillard something to eat."

  "Can do," Nye said. "But it will take a couple of hours."

  "Anything else new?" Mason asked.

  "That seems to be it at the moment, but probably you'd better call Paul, let him know that you're here and that you and I have been in touch-or would you rather I just reported to Paul?"

  "No, I'll call him," Mason said. "Get him on the phone, Della."

  Mason turned back to Nye and said, "Sit back and relax and tell me something about George Winlock, because I'm going to talk with the guy."

  "There isn't much to tell. He's a chap who came here about fourteen years ago and got a job as a real estate salesman. He was a hard worker and a good salesman. He made a couple of big commissions; then he had a chance to tie up some property that he thought was good subdivision property and instead of simply taking a listing on it he took an option-paid every cent he had for a ninety-day option, then got busy and peddled it for a hundred thousand profit. From that time on he started pyramiding. The guy has brains, all right, and he's a shrewd operator. But he keeps pretty much in the background."

  "What about his wife?"

  "She's inclined to be just a little snooty; puts on airs, is just a little bit patronizing as far as the local society is concerned, and while they kowtow to her because of her social position, I have a feeling she wouldn't win any popularity contests if there was a secret ballot, but she'd probably be elected Queen of the May if the feminine voters had to stand up and be counted."

  "What about her son?"

  "Marvin Harvey Palmer is one of those things," Nye said. "We're getting too many of them. He apparently feels that there's never going to be the slightest necessity for him to do any work and he doesn't intend to try. He's an addict for sports cars, a devil with the women, has been picked up a couple of times for drunk driving, but has managed to square the rap somewhere along the line, and- Oh, hell, Perry, you know the picture."