Evil Plan Z - Now With Lemon Scent!

Plankton: Lord knows I've tried. I've exhausted every evil plan in my filing cabinet... from A to Y!
Karen the Computer: A to Y?
Plankton: Yeah, A to Y. You know, the alphabet.
Karen the Computer: What about Z?
Plankton: Z?
Karen the Computer: Z... The letter after Y...
Plankton: W, X, Y... Z. Plan Z! Here it is, just like you said.
Karen the Computer: Oh, boy.
Plankton: It's evil. It's diabolical. It's lemon-scented. This Plan Z can't possibly fail!