The mystery began when Leah's jeep was found almost two weeks after her journey began - wrecked down an embankment in a remote area 90 miles north of Seattle. She had traveled from one coast to the other in just three days. Some of her belongings - checkbook, CDs, guitar - were scattered about. Inside they found cat food (authorities believe she was traveling with Bea, her kitten), a gas receipt and a movie stub from "American Beauty." However, there was no body, no blood, no sign of a struggle. (Cadaver dogs, helicopters and planes, a grid search, bloodhounds and mantrackers have also yielded nothing.) Robbery didn't appear to be a motive because there was several thousand dollars tucked inside a pair of pants in the jeep. Perhaps most peculiar, blankets were draped over broken windows as though trying to keep out rain.

Roberts' friends and family say she had been on a spiritual quest. Both parents had passed away a few years before and Leah had been in a near-fatal car accident in between the two deaths. Leah had dropped out of school a few weeks before her road trip - instead spending her days at Cup 'O Joe, a local coffeehouse in Durham, North Carolina. There, she spent hours writing in her journal and creating poetry about searching for the meaning of life. She was especially enamored of l950s beatnik Jack Kerouac and loved "Dharma Bums" - Kerouac's 1958 autobiographical novel about giving up a middle-class life and one that takes place in the area in which Leah disappeared. In fact, the note she left behind to her roommate had the face of a Cheshire cat on the front and said, "No, I'm not suicidal. I am the opposite. Remember Jack Kerouac?"

An anonymous tipster called investigators a few days after the disappearance and said his wife had definitely seen Leah at a Texaco gas station in Everett, about 30 miles from Seattle. She appeared, he said, to be confused and disoriented. Cops consider the sighting valid - but before they could get more information from the man, including his name, he panicked and hung up.

Friends and family say there are numerous theories regarding exactly what happened to Leah. Perhaps the accident was staged, or perhaps Leah got out of the car alive and hitchhiked a ride out with the wrong person. It is also possible that Leah might have suffered some sort of traumatic head injury and is living on the streets. Others think that she may not have even been in the car when it crashed - instead, dying accidentally or purposefully at the hands of the person who was last driving the Jeep. With her parents deceased, the search to find Leah has been spearheaded by her brother, Heath, and sister, Kara. They are offering a $10,000 reward.

If you have any information about the disappearance of Leah Roberts, please contact the Watcom County (Washington State) Sheriff's Department, or call the Unsolved Mysteries hotline, 1-800-876-5353.