"The Immunity Syndrome" was the 48th episode of Star Trek: The Original Series, the 19th episode of the show's second season, first aired on 12 January 1968. The episode was written by Robert Sabaroff, directed by Joseph Pevney and novelized in Star Trek 9 by James Blish.


Captain's log, stardate 4307.1. 
Approaching Starbase 6 for a much needed period of rest and recreation. The crew has performed excellently, but is exhausted. And I, too, am looking forward to a nice period of rest on some lovely… planet.



Episode charactersEdit

Clifford BrentChristine ChapelPavel ChekovBill HadleyJames T. KirkJohn KyleRyan LeslieLeonard McCoyMontgomery Scottspace amoebaSpockNyota Uhuraunnamed Starfleet personnelunnamed USS Enterprise (NCC-1701) personnel

Novelization charactersEdit

Christine ChapelPavel ChekovJames T. KirkLeonard McCoyMontgomery Scottspace amoebaSpockNyota Uhura

Starships and vehiclesEdit

USS Enterprise (Constitution-class heavy cruiser) • Galileo (class F shuttlecraft)
Referenced only 
USS Intrepid (Constitution-class)


Gamma 7A (the galaxy's Alpha or Beta Quadrants)

Shipboard areasEdit

USS Enterprise 
bridgetransporter room

Races and culturesEdit


Technology and weaponsEdit


Materials and substancesEdit


States and organizationsEdit


Ranks and titlesEdit

captainchief engineerchief medical officercommandercommanding officercommunications officerdoctorengineerFederation Starfleet ranksFederation Starfleet ranks (2260s)first officerlieutenantlieutenant commanderhelmsmanmedical practitionernavigatorofficerscientistscience officersecond officerweapons officertactical officer

Other referencesEdit

amoebaanatomybacteriabeamingBonesbootcaptain's logcaptain's log, USS Enterprise, 2268clothingfive-year missiongermgovernmenthumanoidjumpsuitlife spanlifeformlog entrylogicmattermemorymicrobemicroorganismnation-statepantsplanetraces and culturesrankregulationpersonal logpersonal log, Spockpersonal log, James T. Kirkspacestarstar systemstardateStarfleet uniformStarfleet uniform (2260s)suicidetechnologytitletunicuniformuniversevirusweapon


earlier in 2268 
Intrepid journeys to Gamma 7A. (prior to episode/novelization)
stardate 4307.1, 2268 (2260s chronology, 2264–2270 Enterprise voyages
Enterprise travels to Gamma 7A.
24th century 
Starfleet officers recall Kirk's account of this incident. (NF novel: Martyr)


Related mediaEdit

Many Starfleet officers believed the logs of this incident were made up by James T. Kirk and have little or no base in reality. (NF novel: Martyr)




published order
Previous episode:
TOS episode produced Next episode:
A Piece of the Action
Previous episode:
A Piece of the Action
TOS episode aired Next episode:
A Private Little War
Previous story:
The Return of the Archons
Star Trek 9
Next story:
last story
until Star Trek 10
chronological order
Previous Adventure:
Art of War
Memory Beta Chronology Next Adventure:
The Enchanted Pool
Previous Adventure:
The Rings of Tautee
Pocket Next Adventure:
The Enchanted Pool
Previous Adventure:
The Patrian Transgression
Voyages of the
USS Enterprise (NCC-1701)
(2264 to 2270)
Next Adventure:
Planet of Judgment

External linksEdit

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