With his toolbox and an ice chest, Ernest Nelson was a familiar face at UCLA's medical school. For six years, Nelson would take his gear up to the seventh floor, where the school maintained a large refrigeration chamber filled with cadavers neatly hung by their ears on metal rods. Using scalpels, scissors and electric saws, the former autopsy technician would expertly slice off hands, knees and other body parts and pack them in coolers for later shipment to one of 80 clients, including a subsidiary of medical giant Johnson & Johnson. Between 1998 and 2003, Nelson removed parts of 496 cadavers, says his attorney, Greg Hafif. In exchange, Hafif says, Nelson paid out cashier's checks to the head of UCLA's Willed Body Program, Henry Reid, totaling a hefty $704,600.

While Nelson's activities seem drawn from a Stephen King novel, scenes like this are common at medical schools across the country: bodies donated to one university are shipped, in whole or in parts, to other schools and research facilities. But at UCLA, police say, Reid, 54, was engaged in an illegal scheme to profit from the sale of the body parts. He was arrested a week ago on suspicion of grand theft; Nelson, 46, was later hauled in for suspicion of possessing stolen property. Attorneys for both men say they broke no laws.

The scandal has put a spotlight on a murky trade that is both necessary and underregulated. And it raises ethical questions about how much information universities should disclose to families about the ultimate use of their loved ones. "It sickens me," says Cassandra Angelino, whose mother left her body to UCLA a year ago. Even as aggrieved families were bombarding the school with questions last week, news broke that six corpses from Tulane University's med school had been blown up in 2003 during Army testing of footgear designed to protect soldiers from land mines.

A growing number of anatomy classes use computer simulations instead of actual corpses these days. Still, demand for body parts for medical testing and research remains high--and has given rise to a shadowy band of middlemen like Nelson. He apparently paid Reid about $1,400 per body, which Nelson's attorney says covered handling "fees" despite the fact that the checks were made out to Reid, not the university. Reid's attorney also insists the payments were legitimate. "It's a bunch of finger-pointing with the university and this guy Nelson trying to find a fall guy," says Mel Sacks. But the school says otherwise. "We think this is a dispute among two persons who both were acting illegally," says Louis Marlin, an attorney for UCLA.

Ethicists say the only way to prevent future scandals is to bring more transparency to the process. University of Pennsylvania bioethicist Arthur Caplan says he would force companies to reveal exactly where they obtained body parts. "That would clean up the field pretty fast," promises Caplan. Universities will also need to be more upfront with donor families. Tulane never told families that it was sending excess cadavers to a company called National Anatomical Service, which in turn sent six of the bodies to the Army last year for a total fee of $25,000-$30,000. In a statement, Tulane says it has "discontinued its relationship" with NAS, but the firm's president, John V. Scalia Jr., insists his company did nothing wrong. Tulane and UCLA have promised to improve their oversight, but it will be a long time before they can put families' minds--and souls--to rest.