Grauwulf seemed not to notice the rolling and pitching of the boat. His elbows rested on the front rail, fingers entangled in his shaggy beard.

To his left, the watch scanned the blue with Zeiss binoculars - attempting to mask his fear with concentration. Behind, on the birdcage, two more seamen stared up at the sky - one, his arm draped protectively over the grey breeches of the twin 'zwillingkanonen.'

A stiff breeze whipped spray up and over the hull, sending foamy rivulets slopping into the scuppers. The boat thrummed and shook with each roller.

Metal studs clanged on the ladder and a black balaclava appeared through the hatch. Grauwulf took no interest as the man staggered forward to grab a spare piece of rail next to his captain.

"Eagle, sir!" the man shouted. Grauwulf turned his face slightly - the man continued. "Vessel is a President Line mail steamer, 9000 tonnes. Continues westerly course at approximately 22 knots"

Grauwulf acknowledged with a tip of the head. The man waited for a reply.

"I will go below in a minute," he told the man, eventually. "Tell the exec I want to see him in the chartroom."

"Sir!" the man shouted before scurrying for the hatch.

Grauwulf resumed his position before slowly coming to attention. He leaned towards the watch.

"Keep your eyes peeled," he shouted before staggering back towards the hatch.

The metal ladder was slippery from the seaspray that found its way over the tower. It was a known, and Grauwulf made sure of his purchase as he descended.

The contrast between the freshness of topside and the stench below was momentarily disconcerting. Grauwulf strode aft- behind the steel partition that surrounded the map table. His exec waited for him. "Anything from Zeebrugge?" he asked his second officer.

"Nothing." The exec shook his head. "Not since general operational orders last night."

Grauwulf clicked his tongue. He stared at the chart in front of him and at the three pins stuck there. He picked up the dividers and ruler and lay them between the markers.

"22 knots," he sighed.

"Yes, G."

"There would be only time for one shot at it, Otto."

"If it stays on that course and speed - I think so."

"So, we move to this position, no?" The exec nodded as Grauwulf pushed in another pin. He linked the two points with the rule and calculated. "One hour, I think," he said - more thinking out loud than to anyone in particular. "Can you find me the general instructions as regards neutral shipping?

"Sir, I can quote chapter and verse."

"Just read it to me, Otto."

The exec took down the folder pinned to the hessian board behind them. He quickly leafed through until he came to the relevant passages.

"Ah ... all shipping transiting the War Zone are to be regarded as belligerent regardless of whether they sailed from an enemy port or not. The Reich Government has issued warnings to all shipping..."

"Yes, yes," Grauwulf interrupted. "And what of passenger steamers?"

"Ah ... passenger vessels are to be stopped and searched. Those flying enemy flags may then be sunk after sufficient provision has been made for the safety of civilian passengers."

"And what if they choose not to stop?"

"They may be sunk without further warning."

"That piece about 'safety of the ship', Otto?"

"Commanders are reminded not to expose their vessels to unnecessary risks in offensive actions."

"That's the nub of it, Otto. That is the carte blanche. How do we judge 'unnecessary risks?' War involves risk, unnecessary or otherwise. It is bullshit! To remain on the surface is 'unnecessary risk'."

"We need to charge batteries, G."

"Yes, and we are too slow submerged to reach our attack position. If we attack in daylight on the surface we risk attack."

"A risk we must take to follow our operational orders, G?"

"A 9000 tonne vessel moving at 22 knots cannot stop for our hails. We are too slow to keep up let alone overtake her. To 'stop and search' is bullshit. We are commanded to sink her without warning. That is what our general operational orders say, in effect."

"So be it," the exec shrugged. "All neutral shipping has been informed about the war zone. They want to take the risk - they suffer the consequences."

"Women and children? They are 'consequences'?"

"Their parents took them on board, G. The shipping line then sailed her through a zone where they are liable to attack. This is not our responsibility."

"Not our responsibility? I kill a passenger liner full of civilians and I bear no responsibility? Why, because the Fuehrer says so?"

"The Fuehrer directs and the High Command issues orders. We do what we're told - that's the way of it."

"There was once something called 'an illegal order'."

"Sure, G, and Germany was defeated in the first war observing these 'illegal orders'. Things are different, now. We must put our personal feelings behind us. The military teaches us that."

"The military never taught me to sink a ship load of women and children. There was room for humanity, nobility."