MCCOY: Go easy on her, Jim. She's in a pretty bad state.
KIRK: I'll try.
(Scott and Mira enter)
KIRK: Lieutenant Romaine.
MIRA: I didn't mean to be unco-operative, Doctor.
MCCOY: Of course you didn't. I told the Captain.
KIRK: We must get to understand what is happening.
MIRA: I'll tell you everything I know.
KIRK: Ship's investigative procedures are sometimes confusing to a new crewman. Don't let us upset you.
MIRA: I trust all of you implicitly. I want to help.
KIRK: This investigation has been prompted by two events. First is the time you passed out on the Bridge, and the second is when we fired our main phasers into that force that is attacking us and seriously injured you.
MIRA: You mustn't worry about hurting me.
KIRK: Now this is how we'll proceed. Mister Spock has all the information available to us about our attackers. Doctor McCoy has access to Starfleet's exhaustive files on you. A comparison of the two may turn up some improbable connection which may protect you and ourselves. All right, gentlemen? Doctor McCoy, will you proceed?
MCCOY: Romaine, Mira. Lieutenant. Place of birth, Martian Colony Number Three. Parents, Lydia Romaine, deceased. Jacques Romaine, chief engineer, Starfleet, retired.
KIRK: Mister Spock, are you prepared with the background history of the attackers?
SPOCK: I am, Captain. I have fed all obtainable data to the main computer. It should be ready to supply whatever conclusions are possible.
KIRK: Thank you. Mister Sulu, what is the status of our friends?
SULU [on monitor]: Status unchanged. They're still with us and keeping the same distance.
KIRK: Continue evasive manoeuvres. Keep me informed. Kirk out. Doctor, do you have a medical record of Lieutenant Romaine available?
MCCOY: Yes, Captain.
KIRK: I'd like a few items from her psychological profile checked. Any history of psychosomatic illness?
MCCOY: Occasional and teenage routine incidents.
KIRK: Any evidence of involuntary or unconscious telepathic abilities?
MCCOY: None.
KIRK: Any pathological or unusual empathic responses?
MCCOY: No, Captain, not empathic. However, an extremely flexible and pliant response to new learning situations is highly marked.
KIRK: Go ahead, Doctor.
MCCOY: After our phasers hit that thing, I gave Lieutenant Romaine a standard Steinman analysis. The results might be interesting.
KIRK: Go ahead.
MCCOY: The comparison of our Steinman with Starfleet records shows that Lieutenant Romaine's fingerprints, voice analysis, all external factors remain exactly the same as before. However, according to two hyperencephalograms, her brain wave pattern has been altered.
KIRK: That's impossible!
MCCOY: That's what I was taught. But the BCP is just as consistent as fingerprints.
KIRK: Let's see it.
(A jagged graph comes up on the monitor. Spock raises an eyebrow)
SPOCK: Doctor McCoy, according to your records, Lieutenant Romaine showed no abnormal telepathic powers.
MCCOY: That's right, Spock. But exceptional pliancy was indicated. That might be a factor.
SPOCK: And you are sure that this is the correct slide?
MCCOY: Yes, Mister Spock. That is tape deck D, brain circuitry pattern of Lieutenant Mira Romaine.
SPOCK: Gentlemen, it also happens to be tape H, the impulse tracking obtained from the alien life units.
MCCOY: Nurse Chapel followed this every step of the way. There can be no error.
KIRK: Check it, Spock.
(Spock puts his computer disc in, and the two patterns overlap and match exactly.)
SPOCK: As I said, Captain, this is the tracking obtained during the last shielded run. Computer, run a detailed comparison brain circuitry patterns, tape D and tape H.
COMPUTER: Comparison tape D's brain circuitry patterns of Lieutenant Mira Romaine and tape H, brain circuitry patterns of alien life unit, identical. Identical.
SPOCK: Fascinating.
MCCOY: There has been no error.
SPOCK: Doctor McCoy is correct, Captain. There is an identity of minds taking place between the alien beings and the mind of Lieutenant Romaine. Their thoughts are becoming hers.