Just before its junction with the older sewer, the tunnel Sebastian followed opened out into a broad basin so wide the water only ran down the middle, with flat banks of deep mud stretching out to either side. Finding a shallow embrasure in the brick wall beside him, Sebastian drew back into the shadows, eased the dagger from his boot, and waited for the two men following him to come abreast.
He didn’t have long to wait. The patrician-nosed gentleman Sebastian had seen in Smithfield passed first. Bledlow, Portland had called him. He carried the lantern thrust out before him at the end of a straight arm that shook so violently the light wobbled drunkenly over the curving walls and ceiling. Sebastian held himself very still and let the first man pass.
The handle of the knife felt smooth and hard against Sebastian’s palm, the chill from the dank earth around him seeping through his sweat-dampened clothes. He waited until the second man—the dark-haired, craggy-faced assailant from the Strand—had taken one step, two, beyond the embrasure. The man moved clumsily, the scuffling of his feet on the slimy, uneven brick making enough noise to cover the whisper of sound as Sebastian slipped from the embrasure.
Catching the second man from behind, Sebastian clamped his left hand over the man’s mouth and slit his throat, the blade slicing swift and sure.
The man died instantly. Sebastian quietly eased the body down to the muddy bricks at his feet. But something in the man’s pocket clunked against the ground loud enough to bring the first man—Bledlow—around.
“Oh, my God,” he yelped. Swinging the lantern like a weapon, Bledlow charged.
Ducking the edge of the lantern, Sebastian sidestepped the lunge. His foot slipped on the slimy bricks and he went down on one knee, the knife spinning out of his hand. Whirling around, Bledlow charged again, the lantern still gripped in one fist. Crouching, Sebastian fell back and used the man’s own momentum to roll him over one shoulder with a heave that sent Bledlow lurching out into the broad mud of the basin.
The lantern flew through the air and splashed into the water, going out. The tunnel plunged into near darkness. Sebastian heard a deep, subterranean rumbling. The mud heaved, sucking Bledlow down.
“Help!” The man floundered in the mud, sinking deeper, to his hips now in the oozing muck. “For God’s sake, help me!”
Sebastian hesitated. He even took an unthinking step off the brick onto the treacherous, sucking muck. But the man had stumbled far out into the muddy basin. Even if Sebastian were to throw himself flat across the unstable silt, his outstretched arms still would not grasp the doomed man’s flailing hands. Sebastian felt the earth shift ominously beneath him. He leapt back.
From far down the tunnel came the echo of a shout and the flicker of a lantern. Portland.
“Quit struggling and try to keep still,” Sebastian said, although he knew the man was beyond listening, beyond reason. Already the mud had sucked him down to his neck. He was screaming, the shrieks punctuated with quick, gasping sobs.
Sebastian regained his footing on the brick and broke into a run.
The light filtering down through the gratings had dimmed with the approach of evening. Soon, Sebastian realized, it would be night. And with the fall of night would come the rising tide.
Reaching the main culvert, Sebastian turned left, moving away from the river. The water here was already running deep and swift enough to carry a man away. He kept to the narrow elevated footpath that ran beside the chasm. But the path was treacherous, its stones broken and crumbling, forcing him to slow down. It wasn’t long before he saw the flare of a light behind him, heard Portland’s loud, angry voice. “Leave him! There’s nothing you can do for him. The man’s dead.”
Sebastian pushed on.
At one point he came upon a broad shaft opening to the street above, with a sturdy iron ladder firmly bolted to the damp stone walls. Taking a chance, Sebastian scrambled up the ladder to find the bars on the culvert above soundly in position. Conscious of the passing of precious seconds, he dropped back down and kept going.
A quarter of a mile or so farther on he came to a place where a side tunnel had collapsed into the main vault, bringing down a heap of rubble and dirt that formed a makeshift dam. Water shot over the lip of the cave-in like a waterfall. But when he scrambled to the top of the tumulus, Sebastian found a broad expanse of water that had backed up behind the debris. A subterranean lake stretched from one side of the vault to the other, submerging the footpaths on either side.
“Well, hell.”