I'm looking for an arcade game to which I don't know the name anymore. I have been looking for this game for the past 10 years.

I played this game in Japan, but I believe it was an American game because all the text was in English.
All I can do is provide the info of what the gameplay was like and I really really hope somebody on here will know what I'm talking about.

The game was a versus game. Same idea as Super Smash Bros. Though only 1vs1 or 1vsCPU. You get thrown in a stage, and you pretty much run around and kill the person at the opposite end of the screen. The closer the characters get to each other, the more the stage zooms in (this is similar for super smash bros.)
There was a time limit to each fight. Throughout the fight, the environment constantly changes. For example, if it's a house, the closer the stage gets to the timeout the more it will become damaged and more areas will become available to pick up new weapons. Aside from the house area, I remember a train stage, weapon factory, ship, circus, aquarium looking place.
The characters were all some sort of agents or assassins in disguise. The characters, as far as I remember were, a regular dude, office girl, monkey, old dude in a wheelchair... like a doctor, two blond kids that look like twins, acrobat circus girl that has a pet, a black dude with a metal arm (haha it's not Barret). The player can pick any of them to play the story or just to play versus somebody else.
The general story consisted of you getting a job to assassinate a person. I remember the final boss to the game is the same guy who hired you in the first place to kill everybody else. The last stage was at the big boss' house, he tries to escape through the roof and to a helicopter and then you take missile launcher and shoot down the helicopter.
This is all I can think of, please please help me figure this out.

Thank you!