Leopold: Are you suggesting madam that there exists a law compelling a gentleman to lay hold of canine bowel movements?
Police Officer: I'm suggesting that you pick the poop up.

Charlie: Don't you think it's time you told me who you are. I mean, don't get me wrong, doing the Duke thing with you 24/7 is a blast, but really. Who are you?
Leopold: I'm the man... that loves your sister.

Charlie: We have a saying in the McKay house: "You shake and shake the ketchup bottle, none will come, and then a lot'll."

Leopold: I tell you, that thing is a damn hazard!
Kate: It's just a toaster!
Leopold: Why is it called a toaster when it produces no toast, but simply warm bread, and inserting it two times produces charcoal? The ideal toaster would have one and a half insertions to produce the correct toast.
Kate: You know something? Nobody gives a rat's ass that you have to push the toast down twice, and you know why? Because everybody pushes their toast down twice!
Leopold: Not where I come from!
Kate: Oh, right. Where you come from, toast is a result of reflection and study!

Kate: I don't want it to be Sunday. I want more of this, more 1876.

Kate: What is this?
Darci: It's a reply to Leopold's invitation. You're going, right?
Kate: I haven't decided yet.
Darci: Oh, you haven't decided if you want to have dinner on your rooftop with a duke?
Kate: Who thinks he's from 1876! No! And I would appreciate it if you ....
Darci: Kate, come on, okay? I don't know what this guy did to piss you off but that is the best apology letter in the history of mankind.

Kate: I'm not very good with men.
Leopold: Perhaps you haven't found the right one.
Kate: Maybe. Or, uh...maybe that whole love thing is just a grown-up version of Santa Claus; just a myth we've been fed since childhood. So, we keep buying magazines, joining clubs, and doing therapy and watching movies with hit pop songs played over love montages all in a pathetic attempt to explain why our love Santa keeps getting caught in the chimney.

Kate: I wasted the best years of my life on you.
Stuart: Those were your best years?

Stuart: Maybe the reason I was your guy was so I could help you find your guy.

Stuart: Theoretically, if you go to the past in the future, then your future lies in the past. This is a picture of you in the future - in the past.

[From Director's Cut]
Kate: We make cereal crunchier. We make boring movies shorter. We made Smucker's get the seeds out of their jam. We did that. As far as I'm concerned, we're heroes.

Stuart: We are still in New York.
Leopold: That sir, is not New York!

Kate: So clearly, you must be a man out of time or Sergeant Pepper!

[Talking on the phone.]
Stuart: Are you sitting down?
Kate: [standing] Yes.
Stuart: No, you're not.
Kate: Yes, I am.
Stuart: No, you're not.
Kate: Ye...
[Kate sits down in chair with a thud]
Kate: Okay.
Stuart: I found it.
Kate: What did you find?
Stuart: The portal. A crack in the fabric of time. It was over the East River, Kate, just where I said it would be.
Kate: You found the portal?
Stuart: A portal into April 28th, 1876. I jumped off the Brooklyn Bridge and took a walk in 1876 today. I followed the Duke of Albany around old New York. Are you listening?
Kate: Avidly.
Stuart: This here's the twist, Kate. Here's the kicker.
Kate: What's the kicker?
Stuart: [whispering] He followed me home.

Kate: Why are you standing?
Leopold: I am accustomed to stand when a lady leaves the table.
[So, Charlie gets up]

[Talking to himself]
Leopold: Ah Miss Blaine, you dance like a herd of cattle. You are a rare woman who lights up a room simply by leaving it!

Stuart: You of all people should understand, you're a scientist. I mean, you invented the elevator.
Leopold: What is an elevator? What are you talking... Where the hell am I?
Stuart: I told you, you haven't actually gone anywhere, you're still in New York.
Leopold: That sir, is not New York!
Kate: I'm afraid it is!

[To Charlie]
Leopold: Is it your habit sir, to simply enter a conversation without introduction?

[Has chased and cornered a bag snatcher, while on horseback]
Leopold: I warn you scoundrel, I was trained at the King's Academy and schooled in weaponry by the palace guard. You stand no chance. When you run, I shall ride, when you stop, the steel of this strap shall be lodged in your brain.
[bag snatcher throws down the bag an flees, onlookers applaud]

Kate: Are you for real?
Leopold: I believe so.

Stuart: Women have changed since your time, Leo. They've become dangerous!

Charlie: You want to vex my sister!