The fabric of his gabardine trousers vibrated with each step, as though the joints in his hips and knees were shuddering beneath the burden of the bomb. It was possible that the perspiring young man with the oversized coat was an innocent who simply needed to do a bit of midday shopping, but Gabriel suspected otherwise. He believed the man walking a few paces ahead represented the finale of a continent-wide day of terror. First Paris, then Copenhagen, and now London.

Gabriel ordered Chiara to take shelter in the restaurant and quickly crossed to the opposite pavement. He shadowed the dead man for approximately a hundred yards, then watched as he rounded the corner into the entrance of the Covent Garden Market. There were two cafés on the eastern side of the piazza, each filled with lunchtime patrons. Standing between them in a patch of sunlight were three uniformed Metropolitan Police Service officers. None took notice of the dead man as he entered the market arcade.

Gabriel now had a decision to make. The most obvious course of action was to tell the police of his suspicions—obvious, he thought, but not necessarily optimal. In all likelihood, the police would respond to Gabriel’s approach by pulling him aside for questioning, wasting several precious seconds. Worse still, they might confront the man, a ploy that would almost certainly cause him to detonate his weapon. Although virtually every officer on the Met had been given basic instruction in counterterrorism tactics, few had the experience or firepower necessary to take down a committed jihadist bent on martyrdom. Gabriel had both, and he had acted against suicide bombers before. He glided past the three officers and slipped inside the arcade.

The dead man was now twenty yards ahead, moving at a parade-ground clip along the elevated walkway of the main hall. Gabriel reckoned he was carrying enough explosives and shrapnel to kill everyone within a seventy-five-foot radius.