- Fu Manchu: The entrance to eternity. Beyond that door there is a tunnel which leads directly to the sea. Cisterns of water are poised above it. The touch of a lever will release hundreds of thousands of gallons of water into that tunnel, and combined with professor Heracles' crystals this can transform the entire sea into one gigantic block of ice.
- Dr. Petrie: It's hot in here.
- Inspector Ahmet: Then take your clothes off.
- Dr. Petrie: A gentleman never takes his clothes off in public!
- Denis Nayland-Smith: Ah, Petrie.
- Dr. Petrie: I'm an idiot, an imbecile and an incompetent dolt.
- Denis Nayland-Smith: Did you come all the way to Scotland Yard to tell me that?
- Dr. Petrie: I'm terribly excited but I just found it. It's been on my own bookshelf all these years.
- Denis Nayland-Smith: [reading] Professor A. G. Heracles.
- Dr. Petrie: The world's top authority.
- Denis Nayland-Smith: Well, I dare say, Petrie, buy would you explain why this book of yours has suddenly become so important?
- Dr. Petrie: Because, his theory may give us the clue that we are desperately searching for. Well, you see, he has a theory, that when the chemical properties of ordinary water are such that they lend themselves to transformation and... tampered with... and he goes on to say here... somewhere... yes, here we are: "water, enriched with a crystallized essence, prepared by the methods which are not as yet practicable to man, might dramatically change its temperature to a cold so intense as to be uncontrollable." There, now, provided that you've got sufficient quantity of water the pressure will build up, which will eventually, with the crystals, become, as he says, uncontrollable!
- Denis Nayland-Smith: But these crystals of which he writes, what would they be composed of?
- Dr. Petrie: Possibly a derivative of opium.
- Fu Manchu: [opening line] This is Fu Manchu. Once again the world is at my mercy. I have conquered not only the mysteries of the continent but now of the oceans too. In the tropical waters of the south Atlantic my hand stretches out to turn water into ice - and to transform safety into the deadliest peril. In a few moments the proof of my mastery will be complete.
- Fu Manchu: I have brought you here to save the life of someone whose knowledge I require as a thirsty man needs water. Crystal clear water, doctor Kessler. The name of the person to whom I refer is professor Heracles.
- Omar Pascha: I am Omar Pascha.
- Denis Nayland-Smith: And I am Nayland-Smith of Scotland Yard.
- Omar Pascha: I thought I could smell a policeman.
- Fu Manchu: [immediately after surviving Omar Pascha's attempt on his life] Take him to the laboratory.
- Fu Manchu: [Over the radio] This is my ultimatum; within the next few hours the Bosphorus and the city of Istanbul will be destroyed.
- Dr. Petrie: It's not true! It can't be true!
- Inspector Ahmet: Doctor Petrie, calm yourself.
- Fu Manchu: [Over the radio] The powers of the world have relied upon one man: Nayland-Smith. Nayland-Smith is dead.