William Shatner: "All stations to immediate alert status. Stand by."

Nichelle Nichols: "Standard general alert signal from Star Fleet Command, Captain."

Leonard Nimoy as Spock: "Annihilation, Jim. Total, complete, absolute annihilation."

DeForest Kelley as Dr. McCoy: "I don't know, Jim. This is a big ship. I'm just a country doctor."

William Shatner: "I want facts, not poetry!"

Nimoy: "I have given you the facts, Captain."

William Shatner: "Mr. Spock!"

Leonard Nimoy: "Incredible, Captain."

Leonard Nimoy: "There is no alternative."

Bart La Rue as the voice of the Guardian: "All is as it was before."

James Doohan as Mr. Scott: "Control circuits threatening to overload, Captain."

DeForest Kelley: "Do you know what you just did??"

DeForest Kelley: "I'm a surgeon, not a psychiatrist."

Bart La Rue: "I am the Guardian of Forever."

DeForest Kelley: "I am Leonard McCoy... chief medical officer aboard the U.S.S. Enterprise."

William Shatner as Kirk: "Let's get the hell out of here."

Note: this was the only occurrence of a four-letter word in the original series.

Bart La Rue as the voice of the Guardian: "Since before your sun burned hot in space, and before your race was born, I have awaited... a question."

Leonard Nimoy as Spock: "I see no reason for answers to be couched in riddles."

William Shatner: "At times you seem quite human."

Leonard Nimoy: "Captain, I hardly believe insults are within your prerogative as my superior officer."

Shatner: "Sorry."

DeForest Kelley: "Mr. Spock's the best first officer in the fleet."