In 1940 our nation was fighting for its life.
Hitler's Germany was determined to invade our islands.
And all that stood in the way were the men and women of Britain.
Now a team of experts across France and Britain
are uncovering fresh evidence of their incredible struggle.
We are going to dig up secrets buried for 70 years,
to reveal stories of heroism from Britain's most perilous year.
In the summer of 1940, the public had looked up
and watched Spitfires and Hurricanes winning the Battle of Britain.
But now their eyes turned skyward again, towards an even greater menace.
In the autumn of 1940, German bombers like this JU88 were becoming
an increasingly common sight in the skies above Britain.
Hitler's plan was simple.
Fill the air with thousands of planes just like this
at the head of a relentless bombing campaign.
The idea - to break the morale and spirit of the British people.
So for the next nine months our towns and cities would become the frontline.
The first major raid was directed against London on 7th September, 1940.
The Blitz had begun.
The Blitz brought the war home to every British family,
including mine.
All that lot, that's all as a result of the bombing.
'My dad Cliff was just 10 in 1940
'and lived here on the edge of London in Barnet.'
Which house were you in? We were in that one there.
When the Blitz really took hold, we used to walk up to a park
at the top of the hill just here, Ravenscroft Park.
And you could look across and see the whole of London ablaze.
This one particular night
there was a tremendous explosion.
What it was, it was one of these parachute bombs.
We called them landmines in those days
but they are really parachute bombs.
Two of them fell on Barnet.
One fell on top of an old army barracks just up the road
where there is now a Waitrose standing there. Good God.
And the other one landed on similar apartments to these at the back of us.
Fortunately, well, sadly for them, but fortunately for us,
they were demolished and ours were badly damaged.
What did you see, what did you smell, was there lots of smoke and debris?
There was a kind of acrid smell.
All you could see really...mind you, it was dark so you couldn't see an awful lot,
but we were conscious of the fact that the windows had gone and that sort of thing.
We were protected basically by the ones that were demolished from behind.
Were many people killed? I believe...
I know at least one person who we knew quite well, she was killed.
And... Because we knew her, we knew about that, but I think there were others as well.
There must have been because it was devastating.
The bombing was designed to soften up Britain for Hitler's planned invasion,
and the threat was very real.
Britain's army was in tatters after Dunkirk
and defences were being hastily prepared
with teenagers and old men drafted into the home guard.
But there was another deadlier volunteer force.
Hidden in Britain's countryside was a secret army.
I'm in Yorkshire with local historian Alan Williamson.
And we are searching for one of the secret army's underground bunkers.
What does the entrance look like, what are we looking for?
It's just covered with some concrete slabs.
The original hatch would have been wooden, covered with vegetation.
That's a good clue.
What's that dip over there, would it be on that side?
'The Secret Army based here were local farmers and gamekeepers, men who knew the lie of the land.'
Quite extraordinary, we genuinely can't find it.
I think...
That's a feature. It's brilliant.
It's so secret, it's brilliant.
We really are genuinely struggling to find this, but that's the joy of it.
It's still as effective a hideout as ever it was.
What was that, Alan? It's over here!
Over there? It's not here at all.
Half-an-hour later...
And Alan thinks he's found it.
Ah, there. Yep.
Right. God, do you know what, if you were walking through the woods,
you'd think that was an old drain cover or something. Yes, you would.
'When the Germans invaded, these men would have gone to ground
'to fight his resistance units from their underground bunkers.
'Which, as we have discovered today, are still very well hidden.'
Wow! This is extraordinary. What is all of this all these wooden things?
This is the main living chamber.
On either side, you have three double bunk beds.
As they were. Clearly seen better days.
Look at that, the old springs from the mattress.
These were all built in advance of an invasion, unlike on the Continent,
where they followed up hastily after the invasion. We were prepared.
What's this?
'The bunker is much bigger than I'd imagined.
'In the event of an invasion, 11 men armed to the teeth would have hidden here
'below this Yorkshire forest ready to cause havoc behind the German lines.'
Taps. Taps, yeah.
'It would have been basic but down here they had everything they needed to survive.
'However, in the event of a German invasion they had a life expectancy of just two weeks.'
I suppose the picture to paint is not one of the Dad's Army.
This was the SAS in its emerging form, wasn't it?
Yeah. These chaps were equipped far better than any other organisation in the country,
far better than regular troops.
Each one had a revolver, a knife, knuckle-dusters sometimes.
They had coshes as well.
Sniper rifle, purpose-built silencer to fit on.
This was a formidable weapon.
Was it war without rules? Yes.
A friend of mine's favourite one was the cheese cutter.
You get quietly behind somebody and go like that and it's all done. Job done.
So they did improvise with their own favourite way of killing.
These were highly trained men with the best weapons available,
but they were also taught things outside the normal rules of war.
Combat Without Weapons. That's pretty gruesome.
You've got this picture of this guy upside down on a lamp-post, presumably having been garrotted.
Armlocks.
The elbow break.
This is all fairly serious stuff, isn't it?
Yeah, there's others like smash his face into the ground.
Fatal blows and serious blows frontal.
Look at that - there's a picture of the human body with relevant bits.
Between the eyes is deemed fatal.
Below the ears is termed serious.
Private parts - fatal.
I do find it extraordinary that
often extraordinary times do bring extraordinary things out of everyday people.
But these guys were really committed.
They heartily believed
that in breaking all the rules it didn't matter, they were defending Britain.
The Secret Army were never called into action from their bunkers,
but many would go on to serve in the Commandos and the SAS.
With winter closing in, Hitler postponed his invasion plans
and instead turned his attention to crippling Britain's war effort with an aerial bombing campaign.
Over the next nine months, the Luftwaffe, Hitler's air force,
would target every major city in the British Isles.
Where do you think it is, Chris?
Over there hopefully.
'70 years on and our aviation archaeologists
'Gareth Jones and Steve Vizzard are on the hunt for a German bomber shot down during a raid on Bristol.'
Probably about 20 odd feet down.
Bristol was a prime target for German bombers during the Blitz.
It's more likely to be...
The crashed aircraft our team are looking for was part of a night-time raid on the city's docks.
Take your pick really, there's such a scattering of parts.
Steve is looking for proof that they are in the right place, and he doesn't have long to wait.
Hydraulic pipe.
It's a pipe cap. If you clean that off it will say Argus somewhere around there.
This is what it's all about - a great big Heinkel 111 bomber.
This is what our team are looking for down in Somerset.
Ours was shot down by a night fighter,
it came down from several thousand feet
and hit the ground with such force that a lot of
the softer parts of the aircraft would be pretty mangled,
some of them unrecognisable.
But what we are secretly hoping for is a glimpse of one or both of these -
the great Jumo engines that powered it.
The Heinkel 111 was the most common German bomber used in the Blitz,
but now there are only a handful left - all of them in museums.
It's the fact that these aircraft are so rare that for me goes to the heart
of why our dig in Somerset can offer such tantalising possibilities.
In short, whatever we can find will be a bonus.
Thanks for coming. The dig we've got organised today is a Heinkel
shot down by a Beaufighter, 15,000ft gone into very soft ground.
One thing to watch out for is you've got quite a big machine today
so we've got to keep up the swing of the bucket.
Everybody keep an eye out because the hole could start to cavitate
very quickly like that and the sides could go.
Because the ground here is so soft, the team fear
that the Heinkel engines might have gone in 20ft or deeper.
We are having to use a massive digger to stand any chance of finding them at all.
In terms of what we are hoping to recover, it's an engine aircraft,
it's on fire, it's plummeting to the ground at 200mph. At least.
So all the really heavy items, the engines in particular, we are hoping
they will have been thrust down into the base of the hole.
They would be - the engines, the undercarriage, anything heavy
has that momentum which will hit the ground, penetrate and go on deep.
Then we hope that in turn drags some of fuselage down with it. Gareth.
We think we are onto something pretty big.
You are starting to smell it as well, you can smell the fuel.
You can smell it, can't you?
The digger bucket has struck something heavy and we are barely 4ft down.
The prop blade here. Look at that.
It's curled right over.
Gareth, you must be a very happy man at this point.
Yeah, it's not often you get to find German bombers.
That's really curled over, that's really sharp there.
As it hit the ground you can see the blade has buckled round.
This engine was going so... That's just smashed into the ground.
Look at the condition of that. What strikes me about this is OK, it's twisted and bent,
but it's almost as good as the day it was made in some respects.
The paint is on it. This... Is this aluminium?
It's aluminium prop, yeah. We think when it hit the ground the engine was running.
So this was still turning as the aircraft hit.
And sort of corkscrewed this and bent the blade around.
In a split-second...
Hard to imagine really, but it's spinning round at goodness knows how many rpm, hits the ground,
comes to a grinding halt, the engine itself effectively explodes.
The engine is still trying to run, so the pistons are still going up and down.
But it stops at that instant so the thing just explodes.
Our Heinkel was shot down during a night-time raid on nearby Bristol.
In the autumn of 1940, mounting losses had forced the Luftwaffe to abandon daylight bombing.
Although flying at night reduced their losses,
the Germans were still vulnerable to the RAF's night fighters.
It was one such night-fighter ace, Edward Crew, who shot down our Heinkel.
The Heinkel was carrying a selection of bombs that evening.
It was carrying one big, high-explosive bomb.
All down the starboard side of the aircraft they had canisters of incendiary bombs,
which were these little one-kilo bombs which the Germans dropped literally
thousands and thousands during the war on all the major British cities.
Incendiary bombs were designed to lodge in roofs and set fire to buildings.
They caused the devastating firestorms that spread terror across the country during the Blitz.
We are over 10 ft down in the search for our German bomber from the Blitz on Bristol.
Crunch, crunch. It's more than just an engine down there.
Close to the twisted propeller is wreckage of the engine
we think was still running when the bomber hit the ground. But it's very badly smashed.
That looks like what we were looking for.
It's about a third of one.
A third of one. Yeah.
'This is very frustrating for Steve and the team, as so little of the engine remains.'
That would've just smashed all the gearing to pieces.
Towards the end of 1940, the German raids increased in size and ferocity.
Attacks of over 100 bombers were common, but Britain was not totally unprepared.
It was here in a London suburb, in a top secret bunker
that the RAF co-ordinated their defence against German raids.
I'm meeting historian Andy Saunders.
Standing in this room, which is huge treat, it's a rare survivor.
This room was absolutely vital to being able to understand where
the Germans were, what they were doing and to husband our own forces.
It all looks quite complex but also slightly Heath Robinson, Andy. Yes.
How did it work? The radar stations would've been picking up the raids over the French coast and the Channel
and they would be estimating the numbers and the track of those raids as they came in.
When they crossed the coast, it then was being picked up by the observer corps.
30 enemy aircraft over the Channel. Flying due west.
All that information from the radar stations and the observer corps
would be filtered into here and so the controller can actually see the whole picture.
Talk me through the process.
When the information was translated down to the table here,
the WAF plotters move these little blocks around the table and the blocks are all marked.
These are hostile raids, H for hostile,
and that would be the number of the raids, so we've got H04,
50 plus, that's 50 plus German aircraft
on that particular raid on that track coming in towards Dover.
When you look at the numbers on the hostile side of the board, we've got 40 plus here,
50 plus there, 50 plus, 30, 30, it's a pretty daunting prospect.
How long would it take a German raid to cross the Channel?
At the narrowest point, it's a matter of minutes.
It was clearly vital that all the information they could suck into his nerve centre
was brought in, analysed and reacted upon very, very quickly.
Back at our dig near Bristol, our crashed Heinkel is proof of how effective our defences could be,
but there is still no sign of that second engine.
We'll find evidence where the other engine was even if it isn't here.
We'll keep our fingers crossed that it is here.
We've done about 15 feet now and if we're lucky,
there might still be something there but we're down an awful long way.
What's your hunch?
I think another five feet and we'll locate the other engine.
The digger bucket is almost at the limit of its reach,
when, a few feet further down, we hit another seam of wreckage from the plane.
The one thing that struck me about this whole excavation
is the minutiae that survived, particularly some of the nameplates. You've got a couple there.
I have, this one has actually got
a little bit of an address on the bottom, of Berlin.
Fantastic piece of intelligence. It is actually, yes.
But of all the nameplates and writing we have found on the bomber, one has really struck me.
That's extraordinary. Bosch. Yeah.
I've got a power drill at home with exactly the same logo.
They were going before the war, during and after.
Something like that is recognisable,
even if you don't know the relevance to the aeroplane,
as you say, you recognise it instantly.
After five hours, the team have amassed an impressive haul of over three tons of wreckage.
The best pieces will be cleaned for display in a local museum.
What's that down there? There we go.
Kind of reassuring crunch here would be... That sounds quite interesting, doesn't it?
The teeth of the bucket definitely bit on that.
Yes, there's something substantial.
It's the prize Gareth and the team have been hoping for.
From 30 feet down, the digger bucket drags up the find of the day.
Entombed in mud for 70 years, is the complete engine of a German bomber.
This was the beating heart of the Heinkel bomber,
which was sent to spread terror and destruction in Bristol during the dark days of the blitz.
This has to be the biggest find of the day, Steve.
Are you pleased with how it's gone?
I think we're very pleased, yes.
It's by far the biggest and most impressive lump we've found today.
The second engine, much deeper than the first one.
The first one over here in pieces, which is very shattered.
You can certainly see what's happened, ripped to pieces.
That was the first one we found. We weren't sure if we'd get to the second one, but there it is.
We've found one of the exhaust stacks here.
If you get that end, we can just give it a little bit of a...
I see. This would stick out of the engine cover, as it were?
Yes, this would stick out the cowlings.
But it's quite poignant in a way, because in crews combat report,
it does state he saw the aeroplane initially by the glow of the exhaust.
He'd have actually seen the red glow coming out of these exhausts.
These are what gave it away?
These are potentially, yes.
The very bit that ended up in the aircraft's downfall.
This Heinkel was shot down before it could release its deadly cargo.
But during the blitz on Britain, thousands of bombers did get through.
The horrific experiences of the people of London and Coventry
have been well-documented,
but there are other places which have been largely overlooked.
This is Hull, and I'm here because after London it was the most devastated city in Britain.
A staggering 93% of homes here were damaged or destroyed by the German bombing.
At the outbreak of the war here in Hull, a local girl, Alice Hodgson
joined up as an air raid warden
and she kept a record of every raid that passed over the city.
In the entire duration of the war, she recorded 824 moments
when the air raid sirens would have sounded over the city.
Not every air raid warning resulted in bombs falling on Hull itself, but many did of course.
Throughout the entire war, 1,200 people were killed and over 3,000 wounded.
1940 fills pages of this.
Day after day, sometimes up to four or five raids in 24 hours.
Sunday, Monday, Tuesday, Wednesday, Thursday and as it goes on,
it begins to reflect the terminology of the time.
The thing that everybody knew only too well.
A simple entry, the time of the raid, its duration and one word in the left hand column,
"blitz".
Hull was a prime target because of its docks.
But the real tragedy is that many of the bombs fell
on the houses of ordinary families,
leaving nearly 200,000 people homeless and desperate.
For many, the only protection from the bombs were Anderson shelters,
hastily constructed from sheets of metal and covered in earth or concrete.
I've come to see one of the few surviving Anderson shelters left in Hull.
John. I'm Jules, very nice to see you.
Oh, I see.
'John Langley's father-in-law, Ron Porter, has got one in his back garden.'
Look at that.
Good God. The original.
Corrugated steel interior. Yeah.
They did a very solid job.
'Ron simply never got around to having it demolished.'
You wouldn't think six people could sleep in there every night, would you? But you remember that.
I remember it very well. Very often when we were not expecting a raid,
we would go to our normal bed and be in our bedrooms.
Was that something of a luxury? It was at the time, yes.
Because when the sirens went, Mother and Father would come up and collect myself, as a younger one,
I had an older brother, and we'd be carried down into the shelter with our pyjamas on
and our dressing gown on and just plonked on our bench.
Can you give me a sense of what it was like spending a night in here?
Because you spent, well 2Â½ years worth of nights in one of these.
Roughly 2Â½ years, yes. When planes came over, we knew they were bombers.
The Germans had a different distinct tone
and it was amazing that we all knew this.
We'd see the searchlights, they would be looking for the planes
and when the siren went to say that it was an all clear,
we were all delighted but we'd stop in the shelter until the following morning.
We wouldn't get up and go back to our beds.
How did you feel when you'd go into the city centre and see it ever more destroyed? Terrible.
Hull was really badly damaged.
And for many years, and I'm going to the '60s and '70s,
there was lots of damage still in Hull then that had never been repaired.
This is Beverley Road in Hull, it's one of the main thoroughfares
in and out of the city and it has been for decades.
Every day, thousands of people use it to get to work,
but I bet very few of them know what's behind this hoarding.
It's only by going round the back that you fully appreciate what's here.
This shell of a building is all that remains of the National Picture Theatre,
a cinema destroyed in the Hull blitz.
Wow. I wasn't expecting this.
The heart of the cinema has clearly been ripped out by an explosion.
This presumably is where the stage and the screen was
and then in here, the heart of it,
this is where you came to catch up on the war.
The great Movietone and Pathe newsreels,
bringing in stories from around the world,
trying to inspire the population to keep going.
150 people were in the cinema at the time it was hit.
It was a miracle that nobody was killed.
Shrapnel marks in the brickwork.
And look at that.
Look at those windows.
Shattered glass, splintered at the split second when the bomb went off.
This building is one of the very few,
if not the only civilian building that survives,
still damaged from the blitz.
When you think of all the tens of thousands of buildings destroyed up and down the country,
not just in Hull but in Coventry and Birmingham, the great port cities of Southampton
and of course Portsmouth itself, this is the only one that survives. All the rest of it's been fixed...
..but this little cinema.
However, it's the human stories from the Hull blitz which really interest me.
The oldest person killed here was an 88-year-old woman.
The youngest was a baby, just three weeks old.
I've come to meet someone who experienced the full horror of the Hull bombing.
93-year-old Rita Greendale, who was just 25 at the time, was in her Anderson shelter
with her young daughter, Janet, as well as her rather frightened neighbour, Mrs Bell.
She used to come and say could she come in our shelter because her husband was a policeman
and when the sirens went, he had to go on duty. She wouldn't rest.
She was forever moaning...
She hoped Janet wouldn't wake up, she hoped the bombs wouldn't drop
and she was sure we were going to be killed and oh, she really was dreadful.
She went on and on and on. She said, "I'm sure we're going to be killed.
"Tell Ben I died with a smile on my lips."
And with that, down came this awful noise,
like a whirring noise...
..and that was it. The bomb had dropped on my house.
The force of the blast threw Rita, her daughter Janet,
Mrs Bell and the shelter they were in 30 ft through the air
into the next-door garden, and they were now under a pile of rubble.
And I couldn't breathe. Everything was black.
I could hear people... I could hear voices but I couldn't see anybody, I couldn't see anything.
I'm clinging on to Janet,
trying to move this blanket thing away from her face.
The air raid wardens came and scrambled about and we were dug out.
And Mrs Bell was dead.
And it haunted me
and all I could think about was how awful I'd been,
how nasty I'd been telling her to shut up.
Mrs Bell was one of over 40,000 civilians killed in the blitz on Britain.
Hull was just one of many towns and cities that bravely faced the terror of the German raids.
In the dark days of 1940, our island had stood alone.
We had escaped catastrophe at Dunkirk.
And in the skies above, the heroics of the RAF
had prevented a German invasion and allowed Britain to fight on.
We had survived the most perilous year in our nation's history.
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