So I'm writing a screenplay...

[McC]

It's the mid-1970's. A handful of people are in a diner in a small northern town, a couple customers, the owner and a few employees one morning.

A stranger pulls up, which, in this town, is rare.  He's a very large, sweaty kind of guy, a coronary waiting to happen, dressed in a suit, a suitcase handcuffed to his wrist.  

As he looks in the window before entering, he keels over, unconscious but not yet dead.  Key word yet.

The people in the diner rush outside, look him over, discover he is still alive.  When I say big, I mean 350 or better.   They decide to take his giant ass inside.

On the way in, they drop him on his head a few times and bang his head on everything on the way in.  The finally get him inside, stick him in a booth.  He wakes up, says he has a wicked headache, just needs some aspirin, some water and a short rest.  They go on about their business.

A bit later, after all but one customer is gone, the owner, a young woman barely over 20, passes by him and notices he has passed out again.  Upon further inspection, it turns out he is now dead.  He survived being dropped and banged around but couldn't handle sitting there and resting.

They turn their attention to the suitcase.  Not a briefcase or an attache case but one of those old plaid suitcases with the zipper.  You know the kind.

They find the key to the cuffs and the suitcase in his pocket, open the case, find 3.4 million in it.  (Did some quick research, found out how much dough[in 100's] would fit in such a suitcase).

Now, I started out just seeing a story about people in a small town trying to keep a secret, trying to betray each other, cheat each other, that kind of thing.  Strictly comedy.

Then, when I was having them bury the behemoth, suddenly I decided one of the women shoots the guy who dug the hole, who is stuck in the hole at the time.  "He was there, I was there, I had the shotgun, it just seemed like the thing to do."

Next thing I know, I've killed off two more characters.  Now, I can't stop wanting to kill them off.

 Also, btw, there is a running gag, each time someone new finds out, or someone else disappears, about how much each share is worth. There's a young guy in it who can do complex math in his head.  They look to him for the math.  Eventually, he just blurt it out each time.  I like running gags.

Now here's my question, at long last--

I really want this to be a comedy.  I understand dark comedy and love the genre. 
but how many characters can I kill before it stops being funny?

Also, I would love to hear suggestions for weird, creepy, funny ways to kill off my characters in a rural area in the 70's. Lots of dairy farms and a few factories.  Plenty of open space, country lanes, a river, etc.  You get the picture.

First killing--shotgun down in a hole.

Second killing--same woman shooter shoots a guy who freaks out over the first murder, after he kept calling keeping the money stealing, an opinion nobody else shared.  "I could just see he was gonna be a problem."

Third killing--the diner owner's mother, with whom she has never gotten along, a slightly off center woman, pedals a bike everywhere she goes.  Everyone in town knows her bike. 

She's riding her bike home after the burial, a car comes up behind her, hits the back tire of her bike, throwing her off it, landing her face down in the middle of the road.

The driver, whose face we don't see, gets out of the car, which we really don't see either, finds the woman is still alive,  bangs her head on the road until she isn't any more, drags her into the bushes, tosses the crumpled bike into the trunk.

This is my mystery killer.  The audience will know who the other killers are but not this one.  Haven't completely decided how many this killer will kill.  I know who this person is and it will be eventually be revealed.

It's also important that none of the characters see anything they do--and they are gonna do some vile shit--as wrong in any way.  Just doing what has to be done.

So, there you go.  To anyone who has read this damn book I've written here, which I've tried to keep as brief as possible, unsuccessfully, I love collaboration, invite suggestions and will give credit for input.  

Whatta ya got?

P.S.--

At the moment, I don't think I will ever delve into who the dead guy was or where the money came from.  Does that leave too big a hole in the story?

I want the audience to walk out and then later realize, hey, they never said where the money came from.  Anyway, thank you in advance for any input.