When Chapel "accidentally" falls into Spock's lap, her collar flickers briefly from black and then reverts to its normal blue.
Kirk forces Harry to give him his last two crystals, but when he throws them into the creature's mouth, there are considerably more. But when they're seen going into its mouth, there are two again.
Spock's insignia appears on the wrong side in one shot as Kirk approaches the rock creature. In the next shot where Spock is in the same position, his insignia is back to the correct side.
During the fight between the two rock monsters, there is a short shot that shows Nurse Chapel, Harry Mudd, Spock, and a unknown red shirted crewman instead of Captain kirk, who should be present.
Kirk: You think Harry Mudd is down there, Spock?
Spock: The probability of his presence on Motherlode is 81%, plus or minus .53.
McCoy: Why can't you just say, "Mudd's probably there"?
Spock: I just did, Doctor.
Mudd: Welcome to Motherlode, gentlemen. Interested in purchasing a little love?
Kirk: We're interested in you, Harry, for fraud, illegal drug manufacture, and swindling.
Mudd: As I said, welcome to Motherlode. A charming planet which does not recognize Federation law.
Kirk: I thought we left you on the robot planet, Harry, permanently.
Mudd: Never underestimate the spirit of Harcourt Fenton Mudd. I... borrowed a vehicle...
Spock: "Stole a spaceship."
Mudd: And left to find haven on Elyria 6, a charming planet. An innocent and friendly populace.
Kirk: To whom you sold the Starfleet Space Academy. Harry...
McCoy: Did I ever tell you about the time I saved Captain Kirk's life? Or Spock's? And my dear friend Scotty. And that pretty little Lt. Uhura. I've saved about everybody on this here ship. If the Enterprise had a heart, I'd save you, too. Now let's talk about your heart, my dear.
Kirk: How long does the effect of the potion last, Harry?
Mudd: I... I don't know. Not long according to the creature I swindled... I purchased the crystals from.
Mudd: Think I'll get rehabilitation therapy again?
Spock: I can guarantee it.
Mudd: Well, that's all right. I just hate to leave you all. All my loved ones.
George Takei and Nichelle Nichols are credited, but Nichols doesn't portray Uhura and Sulu is seen but has no dialogue.
Author Stephen Kandel penned both Harry Mudd episodes of the original series of Star Trek: "Mudd's Women" and "I, Mudd". In addition to this episode, he also wrote the episode "The Jihad" for the animated series.
Roger C. Carmel reprises his role of Harcourt Fenton Mudd from the original series.