Three may keep a secret, if two of them are dead.
He's got your number now
He knows just what you've done
You got no place to hide
you got nowhere to run
He knows your life of crime
I think it's suppertime
— Audrey II, Little Shop of Horrors
Selina Kyle: "OK, go ahead. Intimidate me. Bully me, if it'll make you feel big. I mean, it's not like you can just kill me."
Lucille: "...so there's no need to kill him."
Death Squad Leader: "Yes there is, ma'am...once he's told us who else he's spoken to."
Lucille: "What?" [is machine-gunned by the Death Squad Leader]
"All this, because your wife stuck her nose into things that were none of her business."
—Nicole Horne, from Max Payne.
Narrator: "They knew too much."
Keanu Reeves: "We know too much!"
Narrator: "They went too far."
Keanu Reeves: "We went too far!"
Narrator: "...Those are my lines."
Keanu Reeves: "Those are his lines!"
—Pablo Francisco, from his stand-up comedy
"You really are a smart man Lieutenant Colonel. Did you ever think that would be the cause of your death?"
—Envy from Fullmetal Alchemist: Brotherhood
"He knew Johnny's name and
He spoke it out loud
Now Charlie the barman
Has got him a shroud."
—Narrator in the Doctor Who story "The Gunfighters"
"I'm sorry I can't raise you, my friend, but the exact details here need to remain between me and our god. I just thank the Dark One that I didn't need to execute you myself."
"The more that you know, the shorter your life will be."
— Electra, Cowboy Bebop: Knocking On Heaven's Door
"So now ya know. But ya won't live to tell the tale..."
— Stranger,Oddworld: Stranger's Wrath
"First rule of assassination: Kill the assassins."
— Captain Kirk, Star Trek VI: The Undiscovered Country
"I guess now you know too much and that kinda naturally leads to killing."
— Faith, Buffy the Vampire Slayer