Mafia
A mafia boss calls his life-long assistant into the room "You called, boss?"
(New York accent)
"Alfie, tell me something.... what's 2 plus 2?"
"Uh... 2 plus 2?"
"Yeah, Alfie, 2 plus 2, come on"
"Uh, well, 2 plus 2 is 4, boss"
"It's 4, huh?"
"Yeah... it's 4. Is everythin' ok boss?"
The mafia boss gets out a gun and shoots him.
Some friends rush into the room after hearing the shots.
"Antoni, what's happened? You killed Alfie! Why!?"
The mafia boss replies: "I had to. He knew too much."