Stardate: 3451.9
Original airdate: 9/29/1967
Writer: John Meredyth Lucas
Director: Marc Daniels

Guest stars: none

Nomad the first interstellar probe to seek out new life forms, built by brillent erratic Jackson Roykirk who wished to build an independantly thinking machine, presumed distroyed in a meteor collision. Nomad, after being damaged meets up with.......

"The Other" Tan Ru, an alien probe of great power whose original mission was to secure and sterilize soil samples of other planets as a prelude to colonization.

New purpose of the recombined probes: To seek out imperfect life forms and sterilize them.

Crew Appearances:
Kirk, Spock, McCoy
Uhura (whose memory is wiped clean by Nomad)
Scotty (who is killed by Nomad but is brought back to life by Nomad)
Sulu
Nurse Chapel
Total of 4 security guards are zapped and disappear by Nomad
Mr. Singh, auxiliary control room tech.
Lt. Cortland, security

Story:

Over four billion people are obliterated in the Malurian star system, and the perpetrator is a combination probe and computer identifying itself as Nomad, which has great power, and thinks independantly. Nomad is brought aboard the Enterprise. Mistakenly it believes that Captain Kirk is actually its creator, Jackson Roykirk, and for that reason, Nomad  obeys Kirk's commands. In a Vulcan mind-meld, Spock learns that the machine was actually an Earth probe lost in space centuries earlier which merged with an alien probe. Kirk tricks the machine into destroying itself, using logic.

High energy plasma travelling at warp 15 is the weapon used by Nomad to destroy systems in its path.

symboline Blood Burn, a disease that wipes out populations very swiftly

Uhura sings "beyond Antares"

Spock uses the Vulcan Mind Probe on Nomad

Quotes:
"Non sequetur. Your facts are uncoordinated"
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"You are the creator. The Kirk."
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"My function is to probe for biological infestations. To stserilized that which is imperfect."
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"He's dead Jim." McCoy about Scott after Nomad zapped him.
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"What are the lot of you staring at me for?" Scott after Nomad bings him back to life.

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This subject went on the become Star Trek: The Motion Picture, where an earth probe (voyager) meets up with machines and becomes incredibly powerful returning to threaten the earth.

In the next iteration,  this theme morphs into " The Borg " , machines collecting together to become almost indistructible.