It was so unfair.

Infected with Benny’s excitement, Alan snatched the pages from him and read the good news for himself.

His hands shook and there was a tremor of suppressed emotion in his own voice. “You are right Benny. This is a copy of the order Kaltman would have handed to Kapitänleutnant Helmut Witte. It clearly instructs him to take the Grupenfurer and the unspecified, but top-secret contents of two trucks aboard, and head to Caracas. It goes on to say that he is to follow Kaltman’s orders when he makes landfall. After the mission, he must refuel and head back to resume his original orders to attack shipping from the Panama Canal.”

Alan continued to scrutinise the document. “Benny, what are these other hand-written notes at the bottom?” Benny couldn’t answer, he was so excited. He was thinking in Russian and fumbled for the right words in English.

Alan studied the scribble and official stamps, then let out a gasp. “It looks like the order was not authenticated and the Gestapo have rescinded it, demanding U-159 return to port without informing Kaltman, and to keep him under armed arrest for desertion.

“From the dates, it appears U-159 was unable to establish routine communications with Germany, and the SS ordered another U-boat in the area to intercept.”

Benny pawed through pages in Alan’s file until he came to the list of charges and evidence against Kaltman, compiled by the Gestapo when Kaltman vanished.

“There!” Benny pointed out the paragraphs he was about to refer to. “We knew Kaltman left in one of two lorries with art treasures and bullion, his aid confirmed it. Otto Hemel also provided the list of items loaded onto the vehicles. The Grupenfurer had no military reason to be on a submarine at all, so it makes sense to say he stole the treasures to finance his new life in South America.

“All we need to know is, what happened to U-159?”

“I’m way ahead of you Benny, just give me a moment to do a search.” He typed the search details about the U-boat, into the archive department’s antiquated computer.

After a pause while he read through the results, he uttered a low groan of utter despair. “The vessel was reported sunk with all hands, on 28 Jul 1943 south of Haiti. Let me think now! The Venezuelan Basin is probably 4000 metres deep, so it is going to be a nightmare raising her.”

Alan read the technical details for the IXC type submarine, concluding with a rough mental calculation and added. “It was at sea for 46 days and assuming it travelled most of the time below the surface at, say 4 knots, that would account for roughly 42 days. If Kaltman was headed for South America, Brazil, say…”

Now, Alan’s voice became low and monotone as he spoke his thoughts. “It looks to me like the U-159 was sunk on route, so the cargo would still be aboard.”

Benny grabbed a nearby chair and sat down next to Alan. As he settled on the hard-wooden seat, his enquiring brain leapt to the next question. The Russian’s thin voice sounded quavering and urgent, all the while dreading the answer he was expecting. “Type in the location and check what depth of water she is actually laying in.”

Alan’s fingers rattled the keys on the worn keyboard. Seconds later a map indicated a possible depth. The wreck is shown here in 3600 metres.” Both men slumped back in their chairs with a look of total misery on their faces.

Clinging to faint hope, they did more online searches.

“Look at this Benny. On Wikipedia, it actually describes the attack carried out by the US aircraft. They dropped depth charges and 2 homing torpedoes.