In 1995, Cora made a pilgrimage to the Sanctuary of Our Lady at Lourdes. The site has become a popular destination for believers after the Virgin Mary supposedly appeared there in 1858. "No source of miracle stories has been studied more than Lourdes, France," Randall Sullivan says. "Since 1858, thousands of people have claimed to be healed by the water of a sacred spring. Over 150 years later, there's a Lourdes connection to a phenomenon happening in northern California."

Cora brought holy water home with her and added it to her font. Soon after, a strange and fragrant oil began seeping out of religious statues in her house and into basins and out of the walls. "In November 1995, I came home from work and [made] a sign of the cross. It was dry. Nothing in it. Dried up. And I forgot completely," she says. "The following day I'm going to work [and] there was something in it. It's like consistency of oil. It was so fragrant. It's beyond expression."

VIDEO: Cora explains what happened after her pilrimage to Lourdes.

Cora claims the oil has cured her and others of various ailments. Word of the oil's supposed powers has spread, and people pilgrimage to Cora's home for their own sample of oil. Now, Miracle Detectives Dr. Indre Viskontas and Randall Sullivan travel to California to determine whether the oil is a miracle or an elaborate deception.

Indre and Randall visit Marlene Alberto, Cora's friend who claims a macular hole in her eye was cured by oil from Cora's house. She had a hole in her retina, and was scared to have surgery. Friends introduced her to the oil, which she rubbed on her eye each night as she prayed. When she returned to her doctor, the hole in her retina had vanished.

"It's been gone ever since," Marlene says. "While we are in the office of the doctor, I called up Cora and we cried. I said, I don't know what happened, but I know I've been cured."

"Meeting with Marlene has made both Randall and me more curious about this case. But, for different reasons," Indre says. "So while Randall's flown to Salt Lake City to learn more about the role healing oils play in the Bible, I've invited a building inspector to Cora's house to try to determine how this oil is seemingly appearing out of nowhere."

Building inspector Robert Cox arrives at Cora's house to investigate the curious oils. "The way it's running down the wall makes me believe that it's something in the room," he says. "I've got a portable microscope. We're going to look at the materials itself."

Cox examines the walls through a microscope, revealing a startling finding. "Well, it's not even on the surface," he says. "It goes back to my thoughts that it's splattered onto it."

"Wherever it???s coming from is from inside the room," says Indre. And I think that's an important bit of information that we're now gonna be able to focus on as we continue our investigation."

Next, Indre visits eye surgeon and founder/director of the Retina Macula Institute Dr. Ron Gallemore to discuss macular holes. He says the spontaneous closure of macular holes have been reported, but they are rare. "Some patients will form scar tissue and that scar tissue is a way to heal," he says. "I do have patients who have had spontaneous closure of their holes and have recovered 20/20 vision. But I've seen two in 20 years."

"It turns out that a macular hole healing itself is not medically inexplicable, just extremely rare," says Indre.

Meanwhile, armed with a sample of Cora Lorenzo's oil, Randall pays a visit to Dr. David Stewart, PhD. and author of Healing Oils Of The Bible.

Dr. Stewart points out that the oil can only be a miracle if it is naturally occurring. "God???s oils are not synthetic by definition," he says. "The Bible talks about speaking creation into existence. God said, 'Let there be light.' God said, 'Let there be plants'. When He said, 'Let there be plants', He was creating the oils along with the plants. And He imbued those with his intelligence. If it's natural, it knows how to go into your body and identify the bacteria that are pathogenic and identify the bacteria which are friendly to you."

Dr. Stewart smells the oil, but is unable to identify it. "Do you think it might be a singular substance that is not something we know about?" says Randall.

"Yeah. It does have a floral of fragrance. But, I sure don???t identify the flower." says Dr. Stewart.

"Dr. Stewart believes it's quite possible that this is a substance that no one can identify. It may be a unique substance." Says Randall. "That oil at her house may be the only oil of that kind that exists in the world."

In the final step of her investigation, Indre turns to Joe Nickell, PhD, a professional skeptic and one of the most prominent debunkers of purported, miraculous, or supernatural events in the country. Randall is more hesitant. "I probably approached him with a certain amount of antagonism...science has a wonderful track record of figuring out how things work. It has never told us anything at all about why things happen," says Randall. "I think the, you know, the whole testing God issue comes into it for me."

Despite Randall's objections, the font and statues are wiped down so that no oil is present, and Nickell sets up a time-lapse camera to film any seeping of the oil over 24 hours. While the camera records, a sample of the oil is sent to a lab for testing.

The Results

The lab test reveals the oil contains vegetable oil and a glycol ether. Glycol ether is used in synthetic perfumes in order to keep elements together, which suggests that the mysterious oil is not natural.

Additionally, the time lapse camera recorded no seeping. "No results to report other than there are no results," Randall says. "But we do have to bear in mind this isn't a Feast Day. This isn't a Holy Day. And Cora's story is that the flow is really only present when it's a Feast Day or some sort of Holy Day."

Web Exclusive Video: Joe Nickell sits down with Cora Lorenzo and the Miracle Detectives to discuss how his experiement affects faith.

Although Randall wants to believe, both he and Indre admit there is no miracle in Cora's home.

Indre: What's still a mystery is how the oil got on the statues. We don't have any evidence that someone is putting it there. The fact that you can see the oil on the walls in addition to the statues did seem a little odd. It felt more in tune with sort of the idea that someone is taking the oil and splattering it a little bit. I can sort of imagine that happening. All I know is that from the evidence that I could gather, the oil being on the walls in addition to the statues, the oil coming from inside the room as opposed to some other source, and the oil having this fixative that the perfume industry uses. Those bits of information make this case less likely to be a miracle.

Randall: I suppose that that is the restrained position to take. And I can leave it and just saying I'm disappointed and confused by, you know, the combination of Cora's fundamental goodness that you know it was almost palpable, and her willingness to, to open everything up to us. I mean it was as if she had nothing to hide. And yet, you and I both agree I think that somebody's putting that oil there is the most likely explanation. You know, I'm disappointed. This is not what I hoped it would be.