In a complicated, often frustrating world, wouldn't it be nice if you knew someone out there who had the answers? Someone who could guide you to happiness, wealth or romance, reunite you with a lost loved one, or tell you what might happen next week or next year? How much would you be willing to pay if you truly—sincerely—believed you could harness that kind of power?

Throughout history, people have paid untold billions to biblical prophets and clairvoyant crime solvers, even to market prognosticators who claim they can pick stocks by reading the stars. For those of us who remain skeptical, there are actually organizations that claim to promote and enforce ethical standards among psychics.

At the top of its 8-point code of ethics, the Australia-based International Psychics Association says its members "should give advice as responsibly and accurately as possible."

"Our late founder, Simon Turnbull, always said a reading should cost the same as a good haircut, and that does tend to be a fair guide," spokeswoman Leela Williams said in an e-mail to American Greed.

But, she notes, "Not all psychics are members of our association or any similar group."

That's almost certainly true of some of the most notorious crooked clairvoyants in history. They include a storefront psychic from Oregon who gained control of a valuable, thousand-acre tree farm as well as its owner's heart; a Florida fortune-telling fraudster who was so good that she duped a best-selling author, and many more.

Travel with us into the past and meet some of the charlatans who claimed to see the future, when all they were really looking at was a fast buck.

On late night TV in the 1990s, the commercials were impossible to miss.

"Call me now for your free reading," said the woman with the Jamaican accent in the high-backed chair, her fortune-telling tarot cards spread out on the table in front of her.

"The cards can reveal things that you will never see by yourself!"

In the ads, "Miss Cleo" could be seen answering questions for grateful callers to the Psychic Readers Network hotline. The 800 number for "free" readings was splashed across the bottom of the screen as Cleo identified the father of a caller's child, or told another whether her boyfriend was cheating on her.

Millions of people did call the hotline, whether for a little entertainment or because they really believed Miss Cleo might have the answers. But the readings were hardly free. Callers would find themselves on the hook for as much as $300 per call. And the "psychic" on the other end of the line was not TV's Miss Cleo—who in fact was an actress and playwright from Los Angeles—but one of dozens of contract "readers" who got paid based on how long they could keep a caller on the line.

The Federal Trade Commission got the operation shut down in 2002 after suing the owners for multiple counts of unfair trading practices. Without admitting guilt, the owners agreed to forgive $500 million in phone charges and pay a $5 million penalty to the FTC.

The mysterious 2007 death of hedge fund manager and frequent CNBC guest Seth Tobias at the age of 44 was shocking in its own right. But the battle over his estate would turn into a tabloid scandal, prominently featuring an Internet psychic.

Just after midnight on the day after Labor Day, Tobias' wife, Filomena, found her husband's lifeless body face down in the swimming pool of their Jupiter, Florida home. He died soon after, leaving an estate estimated to be worth as much as $25 million.

Because Tobias had not updated his will after a previous marriage ended in divorce, Filomena's attorneys argued that Florida law entitled her as the surviving spouse to the entire estate. Seth's four brothers, to their horror, would receive nothing.

Enter Billy Ash, a California man who claimed to be the Tobiases' personal assistant. Ash told a handful of reporters that Filomena confided she had hatched a plot to murder Seth by spiking his pasta with the sleep medication Ambien, then luring him to the pool with the promise of three-way sex with a male stripper.

Not only did tabloids seize on the wild story, so did the Tobias brothers, who argued in court that Filomena should be barred from collecting any money because of Florida's so-called "slayer statute."

A CNBC investigation eventually revealed that Ash was not a personal assistant, but Filomena's Internet psychic, who used the tag line "Ask Billy." After Filomena had refused to give him money following her husband's death, he used personal information from their sessions to spin his tale of death by pasta.

Authorities eventually ruled that Seth Tobias died of natural causes, his wife was cleared, and the estate case was quietly settled out of court. Billy Ash was not charged.

One of the oldest tricks in the psychic scam playbook is the offer to remove bad luck or reverse a curse. Rose Marks of Fort Lauderdale, Florida was so good at it that she managed to con best-selling novelist Jude Deveraux out of millions of dollars over a 20-year period.

In fact, Marks was the matriarch of a family of supposed psychics accused in 2011 of scamming hundreds of clients out of approximately $40 million.

The fraud targeted people when they were most vulnerable. For Deveraux, it began when she was going through a painful divorce and started visiting Marks' storefront operation in New York City.

"I kept coming back because she was listening to me, and I had never been able to get anyone to just plain listen to me," she testified in 2013.

Marks told her that "money is the root of all evil," and convinced her to turn over millions in cash and property until she could remove the curse from it—at which point she would give it all back. Of course, the last part never happened—for Deveraux or thousands of other clients.

The Marks family argued that they were simply carrying on a tradition of fortune telling as part of their Roma—or gypsy—heritage, and never meant to defraud anyone. But a jury didn't buy it. Marks is serving a ten-year sentence at a federal prison in West Virginia, following one of the first successful federal psychic fraud prosecutions in U.S. history.

A little bit of desperation can go a long way toward lining the pockets of a mendacious medium. So while few of us in our right minds would visit a storefront fortune teller—in Times Square of all places—hoping to solve our problems, it somehow seemed perfectly rational for Niall Rice, a British Internet entrepreneur devastated by unrequited love.

"Think of a person going through difficult times. Perhaps it's a death in the family, addiction, they could have just been let go from their job, even an illness or physical injury. Each one of those people you are thinking of has the potential to be a future victim of this crime," Rice wrote in a victim impact statement filed in New York Supreme Court earlier this year.

Desperately seeking to reunite with a woman he had met at a drug treatment facility, Rice visited the psychic shop of Priscilla Kelly Delmaro, who milked the situation for nearly all Rice was worth. While the idea of getting ripped off by a Times Square psychic may not be all that surprising, the amount Rice lost to her is eye-popping: more than $550,000.

"I just got sucked in," Rice told the New York Times about the fraud, which continued even after the woman in question had died.

Delmaro served eight months in jail and was sentenced to four years probation after pleading guilty to grand larceny.

Ralph Raines, Jr. was a psychic scamster's dream. A wealthy heir to an Oregon tree farm fortune, he had an almost childlike gullibility. He also believed in psychics.

"I'm interested in—deeply interested in the paranormal. I have a strong interest in it," he told American Greed. "Some of the areas I believe in. Some of the areas I don't."

But that belief was just enough to set up Ralph Raines, Jr. for one of the most outrageous frauds in psychic scam history.

In 2004, he visited the Bend, Oregon storefront of Rachel Lee, who had claimed in TV ads to be a "world renowned" psychic. There, the 57-year-old Raines confided his biggest desire.

"I said I wished I had a family was married and had a family," he recalls.

It was all the opening Lee needed to burrow into Junior's life, and into the family fortune.

To pose as the woman of his dreams, Rachel Lee recruited her 17-year-old daughter, who then convinced Junior he had fathered her son…named Giorgio Armani!

Lee would eventually gain control of the Raines family assets, including the 1,000-acre, sustainable tree farm, which was sold, clear-cut, and subdivided for development.

The scam would go on for ten years before authorities caught on, almost by accident, in a way Rachel Lee somehow could not predict.

She eventually pleaded guilty to conspiracy, and is serving an 8-year prison sentence for a crime that proved that just about the only things these psychics can truly see coming are their victims.

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This article has been updated with the correct name of the spokesperson for the International Psychics Association. It is Leela Williams, not Leela Davis.

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