Anyone who can escape from Satan is a bad ass by definition.

Hi, I'm Paul woozy and I'm a professor of explosives engineering.

And I'm Tassel Obara, special effects supervisor in Los Angeles, and we're back for part two.

We're gonna look even Maur explosions from TV and films from a scientific perspective and a filmmaking perspective, let's look at some clips.

Mission.

Impossible, I think.

A gun, right?

No, no, You mashing together.

Just don't chew it one week quietly.

Get out of here.

I just want to make there isn't really any explosive that that smaller piece would have that much of an effect on people.

This only a certain amount of chemical energy in an explosive for just a few grams.

There's no way you could get that sort of effect.

You mashing together way do have a lot of two component explosives that we actually use.

In this case, it's probable the gum would be explosive, and then the two colors would be two ingredients, and when those were mixed together, that would cause an extra thermic reaction, which means puts up a lot of heat.

The explosive would then be heat sensitive on wood.

Fire is far.

CIA is concerned.

They throw enough money at it and got the technical expertise.

They could probably come up with something but noticed.

Powerful is in the movie.

Wait, just fly out of the scene because it was a huge air blast that blows him out.

But look, it doesn't even affect the tabletops on linen on it.

So that stuff's really good spectral in from a filmmaking standpoint, well constructed scene with Ethan Hunt.

We know he's got stuff up asleep, and we just want to see what it is he's gonna pull out, and sure enough, it pays off and it pays off huge.

The breaking glass is created by a tempered glass, which is the type of glass you'd see in the side window of a car in the United States.

It has a property being very, very strong until any part of it is broken, in which case the whole thing shatters into tiny little pieces, which makes it very convenient for effect Use.

Similarly, when the waiter goes through the glass, you'll notice that the glass is broken before he hits it.

Tempered glass unbroken is very, very strong, and he or she would bounce off it with injuries.

If, on the other hand, the glass is broken, even if it's fractions of a second before they hit it, the glass itself no longer has any structure to it, and they just fly through the fragments and the reverse shot.

Where you see Tom Cruise running away was probably done with dump tanks and likely in anticipation of several takes, they would have went down the whole plaza to avoid a possible continuity problem.

Any time you're going to cause something to get wet, something get dirty.

Somebody get dusty.

If you could dust down or wet down the whole area ahead of time, it's to your advantage, because then you could do multiple takes without having a very time consuming reset.

Whether or not you want to keep that in your pocket, that would be questionable.

Technically, you could make it fairly safe, but this is explosive we're talking about.

It doesn't matter how safe the explosive is because the booms, the boom and that's the dangerous part when it blows up, drive angry.

Now this Nicolas cage has the shotgun from hell here.

Nicolas Cage is from hell here.

That's the cool part.

Now the question is, would a shotgun actually set that off?

I think the answer to that is yet can do if you close enough.

And if you've ever shot a a weapon at night, oftentimes you'll see a big flame come out.

You can even get flamethrower charges the shot.

So in reality, a shotgun could set gas on fire.

But when that trail hits the car, in reality what it looked like his one big wolf.

But in this scene, what we see appears to be multiple charges firing.

What you're seeing here is a very clever combination of several different shots and materials to create the effect that we want.

Namely this apparent chain reaction.

We see the close up of the shotgun strike on the trail of flammable liquid.

And that's a surprisingly difficult effect to d'oh just because it's very susceptible to a wind temperature, conditions and everything else to make it reliable.

And they needed to be reliable because they've got a camera movement on it.

So my guess is that they used some sort of spark charge off to the side so as to create the appearance that the shock and blast was igniting it.

They also seem to have used a different flammable liquid.

There's very little smoke, but you look at the wider shot.

It burns like gasoline.

So then we cut, reset.

We put the explosives in the vehicle, we get Nicolas Cage in the front and we pour out some gasoline to make the trail manually.

Light it.

And while it's burning there, we set it up so that it doesn't burn into the charges that we've set because because we don't want them damaged.

They're triggered electrically and they're triggered in sequence so that first you see the small explosion out to the side.

Just when you think you've seen the full effect, suddenly you get the larger explosion in the background, which is great because you get something that builds visually and thus helps to sell the idea that he is one hell of a badass, so you can see how the smoke looks white, which is a signature of black power.

If you don't mind that white smoke, it looks great.

But if you do, then you probably want to use something other than black, possibly.

Ah, high explosive, which is mainly force and very little visual impact.

That way you could add your own smoke if you needed to.

Chemically or or mechanically current locker.

Nice and hot in here.

Okay, The debts are good.

Laying on the charge.

Nice and sweet.

Good to go.

Put your shop two o'clock.

Dude has a phone.

Put it down.

Put down the phone.

Come on, guys, talk to me.

Oh, what we're seeing is an ordinance disposal team in a war scenario trying to dispose of an improvised explosive device.

And it doesn't go as planned.

They've decided they're going to blow it in place.

It's gonna be too dang gris to defuse or take out.

So they're gonna put another explosive charge on it too sympathetically.

Detonate.

It looks like we don't need a charge.

Oh, I got that figured.

Four blocks.

That'll give us about £20 of bang total in the scene.

They say they've got £20 of bang their bangs A military term for explosives.

Case lang.

I don't think that's £20 there.

I noticed in the scene they're using civilian detonators, rather military detonators and I think the reason for this is that, you know, civilian dead night is like a hell of a lot more sexy than military ones.

Military explosives and military detonators generally olive drab od green.

Obviously, the military want camouflage things they don't want to obvious.

But in the film industry, you want something that pops for the eye.

That ordinary viewer will not know or appreciate.

The difference, though in this film they were trying to be spot on accurate in a lot of places.

So it does surprise me a little bit that they would would make that change.

Yeah, that looks that suit looks like the real thing.

I get to see one twice a year minimum.

These things air immensely heavy.

You're talking about 30 £50.

They're just the suit, and then you've got the weight of the helmet.

That's even without any cooling devices on.

This guy's supposed to be in Iraq, And if it's in the summertime man, he'd be sweltering in sweating inside.

There's only a certain amount of time you can, actually, where the But yeah, you can run in and to actually pass the E o.

D.

School part of it is they land on the back and they have to be able to get up onto their feet from that laid back position.

Have to pass that test for physical fitness.

I think a little bit weird.

They've got this really rickety cart that they're taking out with because that's not usually the way the military operates in this example.

They're breaking procedure.

They send in the robot.

They don't have a problem with robot there.

A problem with the cart should really be sending the robot back in again.

The course it advances the plot.

If the robot could carry the bomb by itself and do it successfully, there'd be no need for the human become in jeopardy, which is the whole point of the scene.

That's probably something they decided would be a convenient way of creating that scenario right there that is wrong.

He places the explosives on top 90 degrees out.

It's completely in the wrong direction on what you want to do with explosives.

Make sure that those plastic explosives are right up against that metal in contact with it, so it can put the maximum amount of shock into that device and make sure that you actually detonated in this direction here, shown in the film.

Okay, it's teeing On the top of its is only a very, very small amount of that explosive actually touching that metal.

See, not gonna get a very good energy transfer.

And it's amazing how much a little air gap will stop a heck of a lot of shock.

That is surprising because I'm assuming they had technical advisors on this, you would think would have noticed that it looks more sexy this way.

Well, no, I don't think it does.

I think it's just the wrong choice.

You know, I don't see why this looks any better visually than doing it right would.

Maybe what we're seeing in this movie's not technically correct.

You gotta understand that the Special Forces guys go now.

That's not the way we do it, but we like it that way because Isis watches these films and they think that's what we do.

It's good, but they get it wrong and movies, because then it's not intel for unfriendly forces.

Appearance of the explosion is quite good in the sense it looks very jagged and violent, and yet they've added a core of what looks like gasoline or some flammable liquid to make it more visually interesting.

You've got our hero in peril, and we get to see not only the explosion, but we also get to see its effects on things like the car body, where the car body is shedding rust and so forth really adds dramatically to this sequence.

I think I'd approach it by creating some sort of dust that looks like rust, placing it on the vehicle and then creating a mechanical shock to that vehicle, somehow with a pneumatic cylinder.

Yeah, beating with a sledgehammer, maybe, but it's a little bit massive for a sledgehammer.

They're all rusted.

Vehicle looks great, But in reality, if you got there blast, What will happen is that material go one way away from the explosion and then get sucked back in towards the explosion afterwards.

No country for old men.

Technically, for this to work, the really should not be that much gasoline in the tank off vehicle because what's going to explode is the gasoline vapors mixed with air.

The actual gasoline vapors push the air out, so it's not explosive mixture inside the tank, so technically a little far fetched.

If we put a rag down into a gas tank, you'll act like a candle.

Then it would continuously suck up gasoline along that, and that would then be burning on the outside the vehicle.

But you certainly wouldn't get a huge explosion.

Contrary to the popular stereotype, at least most of filmmakers I've worked with are very conscious of that.

They want to make a cool piece of entertainment, not an instruction manual, on how to kill your neighbours or for 16 year old kids toe have accidents or anything like that.

So, yeah, they will often try to show something that looks like it would work but really doesn't create the way cool effect that you think it would cause they're going to get a lot of backlash if it does work.

And this extends to stunts and a lot of things like that, where they'll try to pick something that looks visually cool, advances a story but isn't just a huge recipe for disaster.

This whole sequence is a nuanced combination of different effects, both in the actual explosion and in the building, all key together and all without overwhelming the dramatic effect of what we're trying to do, which is sell the idea that this is a distraction, not something that is way cool.

And it's supposed to make us believe in the explosion as the main focus of the scene.

Breaking the glasses again, likely tempered glass broken with detonators to control not only the breakage of it but the exact timing you'll notice.

It does not come as exactly the same time as the car explosion.

There's a slight delay, which is good because you saw the glass break at the same time it's explosion.

It would obscure the explosion, which would be stupid, that glass in the windows full straight down, but in reality, with an explosion of that, we had a blast wave that would break that glass would either push the glass into the shop, okay or reflex into the shop and then rebound on for outside.

But it would not fall straight down like a waterfall, which is the effect you get when you watch it.

Filmmaking is the art of creating an illusion in the minds and the hearts of the audience.

Technical realism on Lee has to be there to the degree that the audience expects it, and when you're a professional and you're doing it for entertainment, you have to think about the audience.

It's important that the audience believes what you're doing enough to be entertained, and that's what we're striving for.