By ten forty-five I knew which twin had broken his fingers. Ronald "Le Clic" Vail ancourt had fractured his second and third left digits in a barroom brawl in 1993. The hospital X-rays showed the injury in the same location as the irregularities I'd spotted on the metacarpals. They also showed that Le Clic's arm bones lacked lines of arrested growth.

A motorcycle accident sent Le Clic back to the emergency room two months later, this time for hip and lower limb trauma. The radiographic picture was similar Ronald's leg bones were normal. His record also indicated he had been thrown from a car in '95, stabbed in a street fight later that year, and beaten by a rival gang in '97. His X-ray file was two inches thick.

I also knew who had not been a healthy kid. Donald "Le Clac" Vail ancourt was hospitalized several times during his childhood. As a toddler he experienced prolonged periods of nausea and vomiting, the cause of which was never diagnosed. At the age of six, scarlet fever nearly kil ed him. At eleven it was gastroenteritis.

Le Clac had also taken his lumps. His dossier, like his brother's, contained a large packet of X-rays reflecting many visits to the trauma center. A broken nose and cheek. A knife wound to the chest. A blow to the head with a bottle.

As I closed the dossier I smiled at the irony. The turbulent life of the brothers would provide a diagram for sorting their bodies. Their many misadventures had left a skeletal map.

Armed with the medical files, I returned to the lower level and took up the parts identification process. I began with the tattooed segment of thorax and the fragments I’d associated with it. That was Ronald. He also got the fractured hand and al tissue containing normal long bones.

Limb bones with lines of arrested growth went to Donald. Limb bones without lines went to his brother.

Next I showed Lisa, one of the autopsy technicians, how to radiograph the remaining fragments with the bones in positions identical to those on the antemortem hospital films. This would al ow me to compare details of shape and internal structure.

Since the X-ray unit was in heavy demand, we worked through lunch, final y quitting at one-thirty when the other technicians and pathologists returned.

Lisa promised she would finish as the machine became available, and I hurried upstairs to change.

Operation Carcajou was headquartered in a modern three-story structure on the shore of the St. Lawrence River, directly across from Old Montreal.

The rest of the complex was occupied by the port police and the administrative offices of the maritime authority.

I parked facing the river. To the left I could see the Jacques Cartier Bridge arching across past Ile-Notre-Dame, to the right the smal er Victoria Bridge.

Enormous chunks of ice floated and bobbed on the dark gray water.