Arthur: Seems to me the title of World's Greatest Escape Artist is a bit oversold.
Harry: And you'd have "deduced" that this was a trap. No doubt it was "Elementary, my dear Doyle."
Arthur: He never said that.
Harry: Luckily, I can hold my breath longer than anyone in the world.
Arthur: Wonderful. Except that the Thames is tidal. We have an hour and a half before the water retreats.
Harry: I'm not saying I'll live, I'm saying I'm gonna outlive you.
Arthur: Quite stirring, your pettiness in the face of adversity.

Harry: You Brits, the way you lie in the name of politeness is charming.

Horace: Why do you two care so much about this?
Arthur: Every time you arrive at the scene of a bloody murder, the first thing you have to do is to find the ones left behind, the ones who have not been physically harmed but on whom all the pain will land. Who've had their loved ones ripped away from them. For ever. But what if that wasn't the truth? Every religion for centuries has told us that death isn't the end. And now, thanks to the many staggering advances in science, we may be able to actually prove it. Nothing is as it was, just 10 years ago. Maybe not even death.
Harry: What a complete and utter load of crap. Death is scary. Death should be scary. Con artists and fools shouldn't be allowed to use the word "science" in defense of a dream.

Harry: People see things, especially young women who've taken a vow of celibacy.
Adelaide: Have you ever met one?
Harry: Yes, but I've never left one.

Arthur: You hoped I was right? You believe in the supernatural?
Adelaide: It's easy for you. I mean, you're a brilliant writer, a brilliant doctor, and you're a man. I worked 20-hour days for years until someone took a chance on me and made me a Constable, and now I've got a desk in the basement, only summoned upstairs to make tea. Until today. What I hoped for was to be able to work just a little while longer, as an actual policeman.

Arthur: If he has something to hide, I imagine he'll run.
Adelaide: And if he doesn't?
Arthur: I imagine he'll beat me rather badly.

Arthur: We were only able to catch our man with the help of a medium.
Harry: Then he isn't your man--garbage in, garbage out.

Arthur: You are a master showman.
Harry: Thanks. I get that a lot.

Harry: I thought you were a smart girl who thought for herself. Now I see you're just a girl. Quit your job and find a man to buy you pretty dresses.
Adelaide: This might be some kind of bet for you, but for me, this is my life. You saw those girls in the laundry. Do you know how many women live in fear of that? This is not just a job for me, it's... ...a hope we can avoid not only those laundries, but something almost as bad, a life of pretty dresses and condescension.
Harry: Well said. Still a stupid idea though.

(to Harry)
Arthur: I was wrong about you. It's not that you think too much of yourself. It's that you think too little. You're afraid that if there's something more, you won't be worthy of it. Why?
Adelaide: How are you supposed to stop a ghost?
Arthur: You find out what it wants.

Harry: I had an epiphany.
Arthur: You know who the murderer is?
Harry: No, but I know how...
Arthur: Then my epiphany trumps yours.

Arthur: Picture tomorrow's headline: "Houdini Can't Escape Watery Grave."
Harry: That is rich, that all the headlines will be about me, not you.

Arthur: I have to admit, Harry, I'm damn impressed.
Harry: Thank you, Arthur.
Arthur: Despite you being an insufferable ass the entire time.

Harry: Equally impressive.
Adelaide: Oh, come on, equally? How about if you include me saving your life?
Harry: Sweetie, I escape from liquid coffins four days a week, twice on Sundays. (to Arthur) I'm looking forward to your new book, my dining room table's lop-sided.

Scotland Yard hired its first female police officer in 1919, not the late 19th century as shown here.