Dr. Doofenshmirtz: So if he's "p" and you're "ooo", together you spell...
Double-0 0: No, they're not O's, they're zeroes, all right?
Dr. Doofenshmirtz: I was just going to say "ooop"... looks like I struck a nerve there!
I Work Alone: Perry seems to dislike working with Double 0-0 due to the latter's bragging of his gadgets he use. Even after being told to work with Double 0-0, Perry finds Double 0-0's methods of stopping villains to be quite useless in nature, such as when Double 0-0 attempts to cut himself out from Doof's trap with his laser watch, Perry flatly throws a brick at Doof's remote to free himself and Double 0-0, who gives credit to his watch, much to Perry's annoyance. He even finds it to be funny when he activated the ejector seat on Double 0-0's car, much to Double 0-0's frustration.
Sherlock Homage: Candace and Stacy wear the classic Sherlock outfit and perform an investigation.
Wrong Genre Savvy: After Agent P and Agent Double 0-0 are free, they have to follow Doof to catch him. There are the stairs that Doof already took. But rather than taking the stairs, Agent Double 0-0 goes up through the inner workings of Big Ben. However, Agent P takes the elevator to beat Double 0-0 to it.