The inspiration for the various topiaries that formed the maze had come from the grand cemeteries of the world. In addition to those in Recoleta, there were examples from Paris and New Orleans. But unlike those elegantly laid out cities of the dead, the necropolis his father and he had constructed was an intricate puzzle with a great secret at the center.

His father had begun the maze of crypts and tombs and burial vaults. Each topiary was a record of a successful mission. Memento mori taken from the targets were buried beneath the various vaults and monuments.

The tokens of the deceased were, of necessity, small. In the early years, his father, the first Piper, had possessed a penchant for jewelry. There were a number of wedding rings, bracelets and watches buried in the maze. Unlike his parent, he preferred more personal souvenirs.

At the start of his career he had gone with the traditional choice—a lock of hair preserved in a small glass box. Over time he had craved more intimate reminders of his achievements. He had settled on a finger from each target. There was more work involved, because each pinkie had to be properly preserved, but there had always been plenty of time for DIY projects between contracts.

For years there had been only his father and himself on the island, but in those days they could come and go freely. Their assignments took them all over the world. But things had started to change after the first Piper died. An unfamiliar loneliness had set in.

He had found a student who had eventually become a friend and a comrade in arms. He and Barrow had worked as a team for a decade. But a year ago things had begun to change—they had begun to change. The prospect of rapid deterioration and death had driven them to the edge of desperation. To survive they needed outside help. That meant taking huge risks. They had made the decision to bring in a small number of students who could be trained to work as assistants. Disposable assistants. The old-fashioned term was cannon fodder.

The Piper found the psychic dissonance produced by the juxtaposition of life and death in the maze stimulating. It disturbed the students, often to the point of panic, but it taught them control—unless it killed them, in which case they became plant food.

The paranormal heat generated by what was left of the old Vortex lab had transformed the cemetery plants in astonishing ways. The foliage grew so thick that it formed impenetrable walls. The natural poisons and toxins produced by several species had intensified over the years. Thorns that in the outside world would have delivered a minor scratch were now stiletto-sharp and just as deadly. The carpets of exotic mushrooms growing inside the crypts beckoned the unwary with dazzling colors and unpredictable radiation.