World War 2 History: John Capes' Amazing Submarine Escape

Updated on July 29, 2017
UnnamedHarald profile image

I try to make history readable and interesting, warts and all. We must look to the past to understand the present and confront the future.

HMS Perseus

Image of the submarine HMS Perseus (1500 tons, 260 ft long) circa 1930s
Image of the submarine HMS Perseus (1500 tons, 260 ft long) circa 1930s | Source

Lone Survivor of HMS Perseus

On December 6, 1941 the British submarine HMS Perseus, struck a mine while on patrol in the Mediterranean. In a short time, she was at the bottom of the sea, a tomb for most of her crew of 59 and two passengers. One of those passengers, John Capes, managed to escape his watery grave via an escape hatch and, finding himself alone, started swimming toward some distant cliffs. Capes' story was so fantastic that, for over half a century, many doubted his claim to have escaped, or even been aboard the submarine, mainly because no one should have been able to reach the surface alive at the depth he claimed.

Magic Carpet Service

Capes' story started much earlier in the war when the car he was driving ran into a horse and cart on the island of Malta in the Mediterranean Sea. Before the incident was resolved however, he was recalled to service aboard the submarine HMS Thrasher where he was Leading Stoker (basically an engine room engineer). In September 1941 the 31-year-old Capes was given leave to return to the island and appear in court regarding the accident. Malta was by then under siege by the Germans and Italians so he was smuggled in by the “Magic Carpet Service”, whereby British submarines were used to deliver supplies and personnel around the Mediterranean. After several weeks he was ready to leave and on November 26 hitched a ride on HMS Perseus, one of the Royal Navy's largest submarines, which was bound for Alexandria, Egypt with orders to patrol the waters off eastern Greece on the way.

Island of Kephalonia, Greece

Kephalonia, Greece:
Cephalonia, Greece

get directions

Perseus Hits a Mine

During the night of December 6, Capes relaxed in his makeshift bunk in an empty aft torpedo rack in the rear compartment of the sub, reading and sipping from a bottle of rum. Perseus was patrolling on the surface in the dark and recharging her batteries off the southern coast of the Greek island of Kephalonia. Suddenly an enormous explosion shook the sub, plunging it into darkness and sending her nose-first almost straight down. When the prow struck bottom, Perseus, whose stern was now almost vertical above the surface, slipped completely under until she lay at rest mostly upright on the sea floor, water rushing in through a great crack in her bow caused by an enemy mine.

Four Survivors and a Bottle of Rum

Capes, thrown about and slightly injured, groped around for the flashlight stored near the aft escape hatch and began looking for survivors. He went forward into the engine room which was full of wreckage and bodies. Ahead he saw that the bulkhead door was shut holding back the sea. The pressure on the other side was tremendous, however, and streams of water leaked through the rubber seals. Capes did manage to find three injured stokers amid the engine room's debris and corpses and helped them further back to the stern compartment. He shut the aft watertight door and the men fortified themselves from his bottle of rum.

Submarine Engine Room

WW2: Two Royal Navy stokers in the engine room of a British submarine during World War II.
WW2: Two Royal Navy stokers in the engine room of a British submarine during World War II. | Source

Dead on the Bottom, 170 Feet Down

Capes located four Davis Submerged Escape Apparatus sets (rubber oxygen rebreather vests) and helped the men don them before putting one on himself. The depth gauge showed they were 82 meters (270 feet) below the surface and the vests were only rated for 32 meters (100 feet). It would almost surely be suicide to try to get to the surface at that depth through the emergency escape hatch, but they were faced with certain death if they stayed. In fact the gauge was wrong. They were actually 52 meters (170 feet) under water-- though still deeper than thought possible to survive.

In order to open the escape hatch, the pressure inside the sub had to be the same as the outside. That meant flooding the compartment. Capes located the starboard bilge valve but it was bent and wouldn't budge. He then remembered the submarine's underwater flare gun which was used to send smoke signals to the surface. Opening its breech, he tried to open the sluice valve. The sea came gushing in and, slowly, the water level rose around them.

Capes made sure everyone had their mouthpieces in and their nose-clips on and, as the water filled the compartment compressing the air at the top, he used a spanner to undo the bolts holding the hatch closed. With a great hiss, the hatch flew open as the trapped air escaped. Capes then guided the others one by one up through the opening before following.

A Davis "Rebreather"

Davis Submerged Escape Apparatus (DSEA) "rebreather" like the one John H. Capes used to escape HMS Perseus
Davis Submerged Escape Apparatus (DSEA) "rebreather" like the one John H. Capes used to escape HMS Perseus | Source


Even with his flashlight the waters were so dark and murky he could only get a last glimpse of Perseus lying slightly tilted on the sea bed. As desperate as he was to reach the surface, he slowed his ascent so the pressure wouldn't build up and burst his lungs. Despite his efforts he became dizzy and the pain in his chest grew ever more intense, every breath hurting more and more the further he rose. When he didn't think he would make it, he broke the surface. Using the feeble light of his flashlight, he searched for his comrades, but found no trace of them. Off in the distance, Capes saw a line of white cliffs. Using his rebreather as a makeshift life vest, he began swimming toward them hoping the others had done the same thing.

A Kephalonian Beach

A beach on the island of Kephalonia (AKA Kefalonia, Cephalonia), Greece in the Ionian Sea
A beach on the island of Kephalonia (AKA Kefalonia, Cephalonia), Greece in the Ionian Sea | Source

Eighteen Months in Hiding

Hours later Capes lay unconscious on the beach beneath the cliffs on the southern coast of Kephalonia. Fishermen from the nearby village of Mavrata found him and hid him in a nearby cave. For the next year-and-a-half, the islanders, at great risk to themselves, cared for Capes. They moved him from house to house and village to village around the island, keeping him hidden from the occupying German and Italian forces. At every turn, when everything seemed bleak, destitute villagers came to his aid. In order to blend in with the populace, he dropped 70 pounds and dyed his hair black. At one point he was given a prized donkey, the only condition being that he not eat the donkey.

Finally, on May 30, 1943, in a plan organized by the Royal Navy, Capes boarded a small fishing boat which smuggled him 640 kilometers (400 miles) to Smyrna, Turkey. He presented himself to the British consulate there and was taken to Alexandria, Egypt and freedom. Capes returned to service in the Royal Navy and later received the British Empire Medal for his exploits. He retired from the navy in 1950.

Too Unbelievable

To say Capes' story was hard to believe is an understatement. Many just did not believe he could have survived an 82-meter ascent. His estimate of where HMS Perseus went down did not square with the Royal Navy's estimate. Some even thought he was an imposter and wasn't on the sub at all. A note was attached to his file:

"The whole of this escape should be treated with reserve, as there are various incidents difficult to account for. Three different authorities who all saw this man separately are doubtful of the whole story. There is no other means of checking the facts and it is possible that this man, who was only taking passage in PERSEUS, may have been on the bridge or in the Control Room and got out before she sank. At the same time there is no direct evidence that his story is not in substance correct."

Till the day he died in 1985, some considered him a complete fraud.


On December 26, 1997 Greek divers discovered the wreckage of HMS Perseus under 52 meters of water several miles from the island of Kephalonia. The cracked hull of the bow was consistent with a mine explosion. The aft escape hatch was open. Further dives revealed no bodies in the stern compartment, an empty bottle of rum and a bunk in a torpedo rack. The sluice valve in the underwater flare gun was open. The depth gauge incorrectly showed 82 meters instead of the actual depth. Even at 52 meters (170 feet), John Capes would have set a new record for surviving a shipwreck. Twelve years after his death John Capes was finally vindicated.

Memorial on Kephalonia

HMS Perseus Memorial, just outside of Poros, Kefalonia (dedicated in 2000)
HMS Perseus Memorial, just outside of Poros, Kefalonia (dedicated in 2000) | Source

“All the survivors of the war had reached their homes by now, and so put the perils of battle and the sea behind them".... (Homer, "The Odyssey", rhapsody a, lines 11-12)”

“Dedicated to the patriotic islanders who put courage before fear to shelter John H. Capes, the sole survivor of the British submarine H.M.S. “Perseus”, which was hit by a mine and sank on December 6, 1941 off the coast of Mavrata, Kefalonia.”

The Story of HMS Perseus

© 2015 David Hunt


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    • profile image

      Phil Griffin 

      18 months ago

      I was just looking at a chart of the Med and noticed the wreck symbols off the south coast of Kelalonia which reminded me of Perseus and whether it is now marked. I did a search to see exactly where Mavrata was and see how close the wreck is off shore. Then I found your article, plus a number of diving experience videos which made me a little sad that the wreck is now a specialist divers tourist location. I hope they are not treading on my uncle Jack's bones. He was an engine room artificer on the boat and may have been with Capes. I attended the dedication of the memorial to the islanders with my father in 2000 and also the plaque on the wall of the community centre in Mavrata which has all the names of the crew. Unfortunately Jack's surname is spelt incorrectly as Griffen instead if Griffin. We didn't tell the organizers. My father was very moved by it. His father had tried for many years to gain information from the MOD about the exact whereabouts of the boat and his eldest son but died in 1985 without knowing. When Capes' story first came out my grandmother believed Jack was one of those that Capes helped and that he must still be alive somewhere.

      Thank you for writing this article. I have the original divers video and the book that was presented to the crew's relatives that attended the dedication. We had a good week on the island and the laying of wreathes was a particularly moving moment for my father. He didn't often cry. Jack was 25 when he died and had been married for 6 months to Molly. My mother and father were in touch with her for the first time in 58 years just after we returned. She gave dad Jack's medals that she had kept. Then they agreed not to meet again. All very sad.

      Thanks again for your article and bringing this to readers.


    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      22 months ago from Cedar Rapids, Iowa

      Thank you for your illuminating comment, Ian. To think he never bragged of his exploits to his mates adds a new dimension to the man.

    • profile image

      Ian Barton 

      22 months ago

      I worked with John Capes he was the most unassuming man you could meet but very impressive to look at with a large beard, he rode an old motor bike and always wore an old army great coat which would fly out when on the bike. Such a nice man as was his wife who also worked at the factory also . I knew nothing of his escape until it was featured in the Sunday paper one w/end. He never spoke about it when I knew him & no one knew anything about him.

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      2 years ago from Cedar Rapids, Iowa

      Hello, Graham. Yes, still on Hubpages, but haven't written much new stuff, though I spend a lot of time updating and submitting to niches. Great to hear from you.

    • old albion profile image

      Graham Lee 

      2 years ago from Lancashire. England.

      Another brilliant hub David. Are you still on hubpages? as well as the others ie owlcation. I have not seen you for some time.


    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      2 years ago from Cedar Rapids, Iowa

      Paul, seeing as the publishing of this book has ties to Kefalonia, I wonder if this is the one you are referring to:

      [Rena Giatropoulou & Kostas Thoktarides, "Submarine Perseus. Escape from death", published by Finatec Ltd for the Prefecture of Kefalonia and Ithaca, (date not specified), in greek language. ISBN 960-8159-07-5]

    • profile image

      Paul Abbott 

      2 years ago

      I met a lawyer whilst out on holiday in Kefalonia approximately 8 years ago. This chap mentioned he had written a book about John Capes including the help he received from the Islanders.

      He also mentioned film rights were being discussed. Does anyone know if this book went to publication?

      Thanks in anticipation.

    • profile image


      3 years ago

      Just returned from Kefalonia and saw the memorial to John Capes which piqued my curiosity in his story. Very interesting

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks for reading and commenting, LongTimeMother. Apparently John Capes was always something of an enigma. He was tall and handsome, graduated from Dulwich College and his father was a diplomat. He was therefore officer material but chose instead to toil as a mechanic in submarine engine rooms. There are pictures of him on the Internet, but I could not not find any that were public domain or I would definitely have included one of him. He seems to have withdrawn after the war and I haven't found anything more about him other than he died in 1985.

    • LongTimeMother profile image


      4 years ago from Australia

      John Capes obviously had some incredible qualities. Caring enough to try and save others, creative enough to find a way to let water in, brave enough to try to reach the surface despite the apparent odds against him, and cunning enough to successfully evade capture. Any idea of what he achieved in his later life?

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thank you, Peg and I hope you do write your Dad's story and publish it on HubPages.

    • PegCole17 profile image

      Peg Cole 

      4 years ago from Northeast of Dallas, Texas

      Fascinating story in exquisite, wonderful detail. I love the fact that Mr. Capes was eventually vindicated for his incredible survival of this wreck. You have inspired me to pen the story my Dad told us about his surviving a submarine that went down and never came up. Thanks and congratulations on Hub of the Day. Well deserved.

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Hi alikhan3. My ears hurt just going down 12 feet underwater! Thanks for the comment.

      Thanks RTalloni. It must have been hard on him to be cast as a liar most of his life. By all accounts he started out as an outgoing personality. At least his legacy was salvaged.

    • profile image


      4 years ago

      Beyond-all-adds incidents are always great reads, especially when they are well written. Thanks for the introduction to John Capes and for a neat report on the story of this aspect of his life. Makes me want to read more details of his life.

      Congrats on your Hub of the Day award, as well.

    • alikhan3 profile image


      4 years ago from Karachi, Pakistan

      Absolutely epic ............ Brilliantly done by Capes as well as you ........ I wonder how would it feel during a 52m accent?

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks so much, Kristen. Like many others, I enjoy researching almost as much as writing-- but there's nothing as satisfying as getting positive feedback.

      moj, his motorcar had demolished the wagon and so when he was summoned back to Malta (via the Magic Carpet) it was to settle the affair with the owner of the wagon.

    • Kristen Howe profile image

      Kristen Howe 

      4 years ago from Northeast Ohio

      David, congrats on HOTD! Your historical hubs are always interesting and amusing to learn about the second world war. Nice lens!

    • profile image


      4 years ago

      but what about the incident with the horse and buggy? was he vindicated for that also? did the trial ever take place?

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks, Geri. The islanders were indeed incredibly brave to hide him for eighteen months from the Italian and German occupying forces. It may sound like an idyllic spot (Greek island in the sunny Mediterranean) but the enemy wasn't kidding around. When the Italian soldiers on the island refused to surrender their arms to the Germans after Italy capitulated, the Germans executed thousands of them.

    • gerimcclym profile image

      Geri McClymont 

      4 years ago

      Amazing story of a real hero. It was quite moving to read how the islanders cared for Capes for the eighteen months he was in hiding, at the risk of their own safety. Glad to hear he was vindicated, even if it was twelve years later. Congratulations on being chosen as HOB --well deserved.

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks Paula! I'm blushing. Hope your new year is happy, too.

    • fpherj48 profile image


      4 years ago from Carson City

      David.....CONGRATULATIONS. Well done! Well deserved! "Happy New Year!"

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks, Joanie. I have to admit when I first heard of Capes' story, I was skeptical too. I was very pleased to hear that the sub was found and proved his story.

    • JoanieMRuppel54 profile image

      Joanie Ruppel 

      4 years ago from Keller, Texas

      Enjoyed this narrative very much. Congrats on your best hub status!

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      hari, thanks for reading, commenting and following. Glad you liked it.

      Graham. always great to hear from you. Thanks for the comment.

    • old albion profile image

      Graham Lee 

      4 years ago from Lancashire. England.

      Hi David. Congratulations! A first class hub as is usual from you. Your research always shines through and you presentation is first class. Well done.


    • shprd74 profile image

      Hari Prasad S 

      4 years ago from Bangalore

      What an emotional story. Excellent adventurous story very well written. Congrats too for being selected by HP editor as best hub. Will follow. Thanks

      - hari

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks, emge, but I wonder what Krishna had against the other 60.

    • emge profile image

      MG Singh 

      4 years ago from Singapore

      Very thrilling tale. I am sure god played a hand in his escaping from the boat for as the Lord Krishna says," not a leaf moves without my will"

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks much, FlourishAnyway. Perhaps the single most compelling evidence supporting Capes' story was the depth gauge incorrectly showing 82 meters while the submarine lies 52 meters under the sea. No one could have made that up. Ironically, the incorrect depth Capes cited (based on the gauge) may have been the very damning detail his detractors couldn't get over.

    • FlourishAnyway profile image


      4 years ago from USA

      What an amazing story of survival, and to have been not believed all those years must have been horrible. Truth is stranger than fiction. Fantastic historical hub!

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Trixie and Larry, I'm glad you both enjoyed it. When a writer's efforts strike a chord in a reader's mind, well, that's what it's (almost) all about. I appreciate your feedback.

    • Larry Rankin profile image

      Larry Rankin 

      4 years ago from Oklahoma

      You always find the most fascinating historical events.

      Wonderfully done!

    • TrixieShi profile image

      Diana Strenka 

      4 years ago from North Carolina

      Great article!

    • alancaster149 profile image

      Alan R Lancaster 

      4 years ago from Forest Gate, London E7, U K (ex-pat Yorkshire)

      David, you could always knit it into coverage on the sinking of the 'Bismarck' off Ireland. 'Hood' was considered unsinkable but for some reason armour plating to protect the magazine had not yet been fitted. She'd been on tour in the Med and was rushed straight into the chase. That could be a story in itself, and the rest built around it.

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Great to hear from you, Alan. I think there were mixed signals regarding Capes: on the one hand his story wasn't believed by many, but on the other hand he was awarded the British Empire Medal. Perhaps the crown awarded the medal based on his 18 months evading the enemy. Re the Hood... our family history has it that one of my uncles was supposed to be aboard her ill-fated run but, for unknown reasons literally missed the boat. I have been unable to verify that. Maybe I'll do more research on the Hood, but I've always felt that particular story was beyond me for some reason.

    • alancaster149 profile image

      Alan R Lancaster 

      4 years ago from Forest Gate, London E7, U K (ex-pat Yorkshire)

      Just shows, doesn't it, that it's hard to convince people if they're set on doubt. It's how the Navy was run: if we say it's impossible, don't try to talk us over.

      Good stuff, David. Good story, much appreciated. One of my uncles lived next door to one of the three survivors of HMS 'Hood'. That might be another good story for you. Up to it?

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks for the compliment, Eric. When I first heard about John Capes, I was disappointed to hear that he was viewed with suspicion, so I dug a little deeper. I'm glad I did.

    • Ericdierker profile image

      Eric Dierker 

      4 years ago from Spring Valley, CA. U.S.A.

      Thank you for sharing that with us in such a great writing style. Really a cool adventure story.

    • UnnamedHarald profile imageAUTHOR

      David Hunt 

      4 years ago from Cedar Rapids, Iowa

      Thanks for your comments, kb and ps. I gather as the years went by that John talked less and less about his exploits, even with his family, but at least they got to see him vindicated.

    • pstraubie48 profile image

      Patricia Scott 

      4 years ago from North Central Florida

      That is quite a story...there just are times that incredible things do happen..I guess that is what makes them 'incredible.'

      Determined, courageous, driven are just a few words that come to mind not to mention that he thought of the others and tried to help them as well in such a perilous situation. Thank you for sharing his story with us.

      Angels are on the way to you this morning

    • kbdressman profile image


      4 years ago from Harlem, New York

      What a neat story! It's too bad he didn't live to see his vindication!


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