When Worlds Collide

The year is 1860...
Humanity is living in prosperity all around the world...
No wars have been tearing through the planet for 300 years now.
Crime has been reduced to zero all over the globe.
But something is happening...

In a pub in Atlantic city, 300 miles from the east coast of America, in the open ocean...

A young man enters with with great speed, rushes to the bartender and draws a gun.
-Give me all you have!
-Please don't shoot!
-I said give me all the money!
During this, in the pub, which was thought to be empty by the robber, there sat John, an experienced hunter. He slowly reached for the gun in his holster. With a well aimed shot, he disarmed the robber, and carried him to the door.
-Thanks John! I think I owe you one again... -said the bartender.
-No you don't...I'm just lucky to have found a pub outlaws prefer.

...Crime has returned to the world, but with no police force (It had been quitted due to no crime) only Hunters could restore order to crime-torn cities...

As John was uploading the data to the net about his new "catch", he noticed something. Water. It wasn't ordinary water. As the drop was slowly sliding down the wall it left a salty track behind itself. John wasnt giving his attention to it, the only that he was interested in was that how much money will he get for his new apprehendition.

The next day, Downtown Atlantic City

John was taking his daily walk through the Downtown, the most criminal part of the city. The once shiny lawn of the Gart University was now dying, because people didnt need its knowledge anymore. Then suddenly it started raining...Something was wrong. The protecting barrier of the city, which protected the citizens of Atlantic City from certain death from the wastes of the ocean, which humans have caused by dumping waste into the ocean, was fading away...
Acidous, salty rain has started falling turning all life into death in its way...

John started to run, he didn't know where to run, but he knew if he stays in the open for too long, he can meet all the criminals he shot down.