I found this kind of crossover, sometime ago around 2 a.m. and thought that if anyone would be able to survive Jigsaw's games, it would be the Joker. And thus went to write.
By the way, this is supposed to be a two-shot. I'll up load the second part later.
Disclaimer: I wouldn't be here, if I'd own "The Dark Knight" and the "Saw" movies. I own nothing.
How to put a smile on your face:
Dry thunder cracked the sky over his head, as John shifted his gaze to look at the dark alley in front of him. It had been a nagging feeling, which had driven him into the darkest parts of Gotham City.
It had been with him since that addict had attacked his wife, tearing at the edges of his consciousness, making him restless as well as making him do things he had never done before; for example: visiting dubious bars.
John sighed and willed his legs to move into the alley.
The darkness wasn't the worst part about this, no, it was the smell. As he entered, John let his eyes roam his surroundings.
The walls were covered in a substance that looked suspiciously as if it was alive and upon closer examination turned out to be mold . He dropped his glance, in order to avoid looking at the disgusting substance that covered the walls.
"Seriously, what makes people neglect their property in a way that it ends up like this?"
Anyway - he instantly regretted looking down, as he was now able to see, where this horrible odor came from. At his feet lay piles of garbage, animals' feces and something that looked like a dead rat... or two.
John Kramer sighed once again. He could go to the bus stop by another route. But this way would take longer and he didn't want to worry his wife by coming home even later, than he already was. Their relationship was already strained.
After he was half way through the alley, the bus stop came in sight. Just as he sighed, this time with relieve – the alley almost behind him - he slipped on something that felt disgustingly soft.
And what made it even worse, was that he had to touch the mold covered wall, in order to prevent himself from falling.
Pulling a disgusted face and wiping his now mold covered hands at the back of his pants, he exited the alley and crossed the street, to get to the bus stop.
As he sat down on a bench, he closed his eyes.
Over the past weeks he had not only developed some kind of chronic abdominal pain, but a headache, too. It was slowly, but steadily wearing him out.
A few minutes he sat there in silence, with his eyes closed and his head resting at one of the metal bars that held the bus stop upright.
Even as he heard a loud crash and hurried steps approaching, he kept his eyes closed; strange things always happened in Gotham.
The bench creaked in protest, as someone threw himself on the seat beside him and the hurried steps stopped.
John heard police sirens wailing in the distance.
Reluctantly he opened his eyes and peered at the person beside him. To him it was a strange person that sat there – even for Gotham's standards – and was breathing hard.
The man was wearing something that looked similar to a faded purple trench coat, with multi colored socks and had... greasy green hair?
As the man turned John Kramer's breath caught in his throat. This man was that wanted criminal that had been in the news for months now, the Joker. He had blown up buildings, robbed banks, murdered people and terrified entire Gotham.
The logical part of his mind told him that he must be having hallucinations, as the JOKER did not just sit at a bus stop, like a normal person would. John shock his head and in that very moment the man beside him began to giggle. A few seconds later he was nearly doubling over with high pinched laughter.
With the Joker bent foreword like this, John could see the bullet wound in his left shoulder.
To John, seeing that bullet wound meant that he didn't have to get his head checked, because that made the chance of meeting the JOKER at a BUS STOP rise from nonexistent to at least possible.
He wasn't seeing things. This was real. The thought that he might be in danger didn't even cross his mind.
John felt anger rising up in him. Criminals like the Joker were free to roam the city. Which could only mean that the police was corrupt and would nowadays just watch as criminals destroyed the city, for the mob bosses paid them, not to intervene.
The city would be destroyed in no time, if no-one would do something. He was so absorbed in his thoughts that he didn't notice that the man beside him had stopped laughing and was now starring at him.
John's eyes snapped back into focus as he was pushed roughly against the back of the den. As a knife was shoved into his mouth, it cut his tongue.
Giggling the Joker spoke, "What do we-he HA HAHA have here?" The blood in his mouth tasted metallic, like steel. John did not reply. "You're supposed to be scared, ya know?" the Joker continued with a nod and some wicked version of puppy dog eyes.
John swallowed the blood in his mouth and tried to push against the Joker's grip. The knife slipped from his mouth and fell to the ground. This led them to struggle for minutes until the Jokers giggles had grown into hysteric laughter and John's head was smashed against a metal bar for a second time this day. But this time the dull pain in the back of his head exploded into a supernova of throbbing and piercing that blinded him for seconds and made him clench his fists in a dead grip around the Jokers arms. Upon seeing this the Joker mocked him, "Whu-hut?"
At this moment something inside John scattered at the taunting sound of the Joker's voice.
The police sirens sounded like they were drawing nearer. "Yes," John thought. "with such people it would be ok." He observed the Joker, as he licked his lips in a disgusting manner.
"Someone has to do the work for the police and with me there will be no criminal that suffers a relapse."
The Joker seemed to also realize that the sirens were approaching them. And with one last shove, the Joker let him go, but not without cutting the back of his left hand with yet another knife.
John lowered his gaze to his hand and was immediately sure that a scar would remain.
He watched impassively as the Joker sprinted away from the bus stop, onto the street, tripped over his own feet and fell down.
"The Joker will forget this encounter. But I will remember this day. As it made me realize something important," John Kramer thought. While watching the Joker getting up and disappearing into the very same alley he had crossed earlier, a smile crept onto his face.
A few months later the news reported about the first "Jigsaw murder".