A scene is a basic unit of scriptwriting; put enough scenes together and you have a sequence. A few sequences and you have an Act - enough Acts and voila! - a script. 

There’s almost a one-to-one ratio of pages to scenes. Checking a few scripts I finished recently I find about 100-110 scenes per script. That’s pretty close. All those scenes need to function at a pretty high level so your script doesn’t get bogged down.

There are many possible scene functions - foreshadowing, information, action, comedic, etc. but all scenes should serve one of four masters for them to work properly:

The principles of scene conflict:
    1) Surprise or Shock
    2) Curiosity 
    3) Tension
    4) Suspense

We would like to have a creative tension in everything we write - this would be an ideal, something to which we should aspire. There are those scenes that you think won’t be shoved into that constraint but it is *essential* never to write a scene just to give information. That’s not film.

So how to elevate our scenes? Apply one (or more) of the four principles to them:

Let’s take the easiest of the four terms to define: surprise or shock. Director Alfred Hitchcock defined surprise as a bomb the audience isn’t aware of under a table suddenly exploding and suspense as knowing about the bomb and waiting for it to explode - good enough for now.

In “The Untouchables” Brian DePalma working from a David Mamet script opens on a little girl going into a bar to get her father some beer. While we’re amused and distracted at the idea of this since something like that wouldn’t happen today, DePalma is quietly at work setting the behind-the-scenes scene.

A man sitting at the bar notices the little girl but says or does nothing beyond exiting the bar. We’re probably still not suspicious of this since it’s such an innocuous moment and mood.

Then the bar suddenly explodes. Welcome to Prohibition Era Chicago. Hold tight - we know it’s going to be a bumpy ride.

That’s surprise - more like shock probably but it wonderfully sets the tone for the film and the Wild West nature of Chicago at that time. If you don’t think something is going to happen in a scene and it happens, then you are surprised or shocked. The ending of the fine little gangster film “Layer Cake” has an interesting surprise in store for us at the end. Check that out too.

Curiosity is easy too. What’s perhaps not easy is applying at least this simple principle to every scene but this is a fundamental - no excuses. If someone is sitting around talking and nothing else is at work in that scene then it’s going to be as flat as yesterday’s beer. Your audience must be curious at the very least about the information and if possible, that information should be setting up a future moment that’s going to work the other three principles into it.

You’re following Clive Owen’s character as he heads for his morning train in the film “Derailed.” Being the whip-smart movie watcher you are, you know this is the setup for something but then again, lots of lazy directors have had entire sequences of people riding a train for no good reason so it may not be anything either.

But it is.

On the train, Owen meets Jennifer Aniston. Since we don’t know either character and there is no emotional charge to this moment, it’s a curiosity moment - how will Aniston and Owen interact? The scene is absolutely necessary but it doesn’t create shock, tension or suspense. It does however pay homage to our little list and create curiosity.

In the incredible film “Girl With The Dragon Tattoo” (the original one) there’s a scene where an old, rather staid gentleman is given some information while walking with another man in a business environment. They end up in a conference room with a woman who we find out is a central player. At this point, we don’t know this. We don’t know why the man is there, who the woman is, why she’s dressed in leather in this corporate environment or a dozen other things. It’s an incredible scene and you could no more turn the movie off at this point than you could an amazing car chase or fight scene - and yet, no one is shot, maimed, slapped or anything else - it’s just people talking. However, the principle of curiosity is applied like a thick layer of Nutella and you eat until you’re full.

Same applies to the opening of the movie in which an obviously rich, old man receives a framed presentation of pressed flowers. He sees the picture, breaks down in tears. Curiosity. We want to know why. Why would something so innocent have such an impact on this man?

Easy enough. Now we get to the knotty two - tension and suspense.

Most of us use the words tension and suspense interchangeably. A dictionary defines them differently as so should we as writers, especially for the sake of our scenes.

Let’s both generalize and specify immediately and say tension has lesser stakes than suspense. Tension is more likely to be a precursor of a suspense scene that either immediately follows or soon after.

An example of both is easy to find in the very well-written “Rescue Me” series.

Okay, so Tommy Gavin, an unrepentant drunk and womanizing firefighter, goes to his on-again, off-again mistress Sheila’s apartment to tell her that they’re finished. Tommy and his wife are reconciling and Janet, the wife, has laid down the law - no more Sheila. Tension is already simmering because we know the history of these two and their wild ways, emotionally and sexually. 

The scene is wonderful. Tommy and Sheila snipe at each other all through, trading insults and hard truth. We sit through it not only because it is well-written but also that given their history of sexual explosiveness we can pretty much figure out where this one is going. Sure enough, after Sheila challenges Tommy’s kissing ability comparing him unfavorably to her current boyfriend, Tommy’s cousin Mickey, they end up on the couch with Sheila’s dress off and Tommy between her legs. So much for his vow to his wife to stay away from Sheila. This is classic Tommy Gavin.

With Tommy and Sheila about to take this current passion to a whole ‘nother level, in walks Mickey, Tommy’s cousin and Sheila’s current BF.

Now there’s gonna be trouble. But not yet - Mickey turns and walks out and both Tommy and Sheila are crazed but for different reasons. End episode.

So, this then is tension, a precursor to the harder-edge and higher-staked suspense. Sometimes you get the convivial partners, tension and suspense, together in one scene or scene sequence. Sometimes they are separated by many minutes or pages. And sometimes you just get tension and no suspense - or even suspense and very little tension preceding it. An example of this would be a killer stalking someone to kill them - say the generic Victim #2, a throwaway character who needs killing. Gotta have some victim fodder. Anyway, those types of scenes can be suspenseful without being tension-preceded.

So, next ep we get the suspense as Tommy goes home to dinner. “Anyone call?” he pseudo-innocently asks his wife, Janet, dreading that Mickey would have called and busted him for being on top of Sheila. “Nope.” “No one, really?” “No, now sit down to dinner.” Tommy does so happily thinking that Mickey didn’t do what he had feared.

Janet calls the other daughter to dinner and when the younger daughter comes into the kitchen, guess who she’s got in tow - yep, cousin Mickey who just “happened” to come by to visit. And Janet has invited him to stay for dinner knowing how much he likes pasta.

This then is suspense as surely as those men have guns under the table aimed at the other. Mickey tortures Tommy, ratcheting up the suspense until it’s almost unbearable. He continually mentions Sheila in seemingly innocuous ways, causing Tommy to choke - or fake it - so he doesn’t have to respond. Tommy does such a good job at faking that he actually begins to choke - now it’s getting physical, which is also another way to tell tension from suspense - suspense ends most times in a physical expression.

Janet yells at Mickey to help Tommy as he’s choking and in the process of giving Tommy the Heimlich maneuver, Mickey is also mercilessly punching Tommy in the kidneys - unseen by Janet and the girls, of course.

And then the trigger to the moment is pulled and the fit really hits the shan - Sheila comes over, sees Mickey beating Tommy and rushes in confessing to Mickey (and Janet) that he saw wasn’t what he thought it was.

A puzzled Janet says that Mickey was just helping Tommy unstick food - what the hell did she mean? Sheila realizing her mistake wilts.

Game on. Now the stakes are even bigger because a new player has been introduced - Tommy’s wife who has been through this many times with him.

Tommy and Sheila are interrogated mercilessly - and this section does go on too long because it reduces the wonderful suspense they’ve built up. But yeah, Mickey finally pops Tommy in the mouth and like the climax to a sexual union, the payoff to the suspense buildup is spent.

  Below, following, is an example of suspense with no preceding tension - but, and this is key, there is implied tension because the characters have been defined properly. And perhaps I shouldn’t say “no tension” because there’s a small build-up to the climax of the suspense - what I really mean is this scene can sit by itself without any earlier setup.

In “Kill Me Again” a neo-noir film about betrayal by John Dahl, Michael Madsen playing the psychopathic, Vince Miller (does Madsen ever play anything but a psychopath?) is trying to find out where his money has gone. It’s in the hands of Val Kilmer and Joanne Whalley-Kilmer who have pretended to be murdered and run away.

The scene, in the middle of the film, opens with Madsen having tied up Kilmer’s friend - the excellent character actor Jon Gries - in a chair. We know that Madsen isn’t a nice guy; we anticipate violence and so it goes. After burning Gries with a cigarette numerous times to force him to reveal the couple’s whereabouts, Madsen summarily cuts his throat. Suspense is delivered on in brutal fashion. There is internal tension to the scene but really no preceding tension.

So, can you see the difference? It’s really degrees mostly. Tension can be a precursor to suspense but suspense is rarely, if at all a precursor to tension. We know Madsen is nutso-cuckoo so the scene with him cutting Greis’ throat doesn’t necessarily create more tension except that we do now know that perhaps Madsen will be that much closer to finding the cheating couple.

And when he does find the couple shacked up in a hotel, there is a tremendous amount of tension, but really, no suspense. Watch the movie to see the scene but honestly you never feel that overwhelming sense of suspense that you did in the scene where Madsen had Gries in a chair. This is an unfortunate function of our medium - you’re pretty sure that no one who is central to the story is going to get killed so suspense in scenes like that is reduced to simple tension.

How about one more example - one that combines all four principles:

The insanely good "The Long, Good Friday" features British mob boss/powder keg Bob Hoskins on the eve of a big deal with an American Mafia counterpart facing disaster; all his pubs are blowing up and he has no idea why.  Having had enough, he orders his thugs to bring in the usual suspects so he can question them.  After gathering, when the next scene opens, said thugs are in a meat locker, hanging upside down.

Shock - who expected these guys to be questioned while hanging upside-down on meat hooks?  It's a moment you will never forget.

Curiosity - what will he do and what will be revealed when he questions them.  We're just as confused as he is although we do have a hint or two that the mob boss doesn't.

Tension - that's pretty obvious.  Hoskins starts off mild-mannered and reasonable but it is amazingly painful and tension-filled to continue to watch these men hanging from hooks while they are being questioned.

Suspense - the longer the scene goes on, the more certain you are of a climax of horrendous proportions.  I won't spoil the scene for you but it's worth the wait - but perhaps not in the way you imagine.

Brilliant, brilliant filmmaking.  You are in nail-biting, skin-picking agony for the entire scene.  This scene - the entire movie - uses all the principles to great effect.

To recap:

   1) All your scenes, to be effective must use of at least one of these four techniques to make them snap. Simply delivering information in a scene will never do. You’ll lose your audience. It’s lazy writing.

   2) All four techniques are also very dependent on timing. It is essential, in fact. Delivering the surprise or shock too late or two soon kills it. Not building suspense up enough really just gives you surprise or shock.

   3) Tension and suspense are dependent on some backstory or understanding of the situation or characters to be effective. Surprise and curiosity don’t really need either.

   4) Tension is not as serious or extreme as suspense. Suspense is going to get someone physically involved, perhaps hurt or killed - tension may hurt some feelings or result in a good bonking but it’s rarely never more than that.

The next time you’re watching a particularly effective film or TV sequence, try to identify one of these four elements. The more you see it, the more you’ll use it.

Good luck.