"Which one ought we to nab first?" asked Ferret. "We'll have to be very sharp, or one of them, finding that he is no longer in communication with his accomplice, would smell a rat and clear out."
"Under normal conditions I would reply, 'Collar the principal first'," replied Hawke. "It is evident that Ramblethorne, alias von Hauptwald, is the master-spy. Directly he's laid by the heels, the whole of the organization immediately under his control goes by the board. But there's this Harwich business. Von Ruhle crosses the North Sea to-night, unless otherwise prevented. We comprise the otherwise, I hope."
"Then it would mean catching the midday express to Waterloo," remarked Ferret.
"Could we go with you?" asked Ross.
The police officers looked rather astonished at the cool request. Like most professional men, they scouted the idea of amateur assistance when the main issue was at stake.
"Perhaps it wouldn't be a bad idea," remarked Hawke. "You have already shown great discretion in the matter. Most fellows would have made a bee-line to the nearest telegraph office and given the whole show away. The only difficulty is—I suppose, by the way, you are not feeling too done up after your trying experiences?—the only difficulty is, I was remarking, that von Ruhle might spot you. Look here, Ferret; suppose you take these young gentlemen, and proceed to Harwich by an ordinary train? Keep well out of sight when you arrive at Parkeston Quay, but keep a sharp eye on the boat. I'll travel from Liverpool Street by the boat train, and see if I can pick out our quarry amongst the passengers."
It was a tedious journey from Plymouth to Harwich. Arriving at Waterloo, Ferret took the lads to a quiet hotel and ordered lunch; while Hawke, excusing himself, called in at "the Yard" to report his new case to the Chief, and to wait for the Great Eastern boat train.
The weather had changed completely during the run from the West, for when Ferret and the two lads arrived at Parkeston Quay it was raining heavily, accompanied by half a gale of wind from the east'ard.
"We've a long wait," commented Ferret. "Fortunately I know several of the Customs officials very well. I'll get them to let you take shelter in their shed. It's almost opposite the berth where the steamer generally makes fast. You'll be able to watch everyone who goes up the gangway. I'll go on board and speak to the steward. I don't suppose we'll spot friend von Ruhle until the boat train arrives, and by that time perhaps Hawke will have marked his man."
Undoubtedly, the wisest course would have been to send other officers to Wellington to arrest Dr. Ramblethorne; but Hawke was out for "kudos". Only a short while ago he had let a wanted man slip through his fingers, and had been rapped over the knuckles for it. With the professional assistance of Ferret, he hoped to carry out a double coup and arrest both German Secret Service agents, thereby recovering his lost prestige.