Campbell's pistol leveled, but Ennis swiftly struck it up. "No, you might hit Ruth."
He and the inspector bounded forward along the pier. Fire streaked from the dark ahead and bullets thumped the rotting boards around them.
Suddenly the loud roar of an accelerated motor drowned out all other sounds. It came from the river at the pier's end.
Campbell and Ennis reached the end in time to see a long, powerful, gray motor-boat dash out into the black obscurity of the river, and roar eastward with gathering speed.
"There they go—they're getting away!" cried the agonized young American.
Inspector Campbell cupped his hands and shouted out into the darkness, "River police, ahoy! Ahoy there!"
He rasped to Ennis. "The river police were to have a cutter here tonight. We can still catch them."
With swiftly rising roar of speeded motors, a big cutter drove in from the darkness. Its searchlight snapped on, bathing the two men on the pier in a blinding glare.
"Ahoy, there!" called a stentorian voice over the roar of the motors. "Is that Inspector Campbell?"
"Yes. Come alongside," yelled the inspector, and as the big cutter shot close to the end of the pier, its reversing propellers churning the dark water to foam, Ennis and Campbell leaped.