- Spock is assigned to the USS Enterprise as science officer. (TOS: "The Menagerie, Part I")
- The Enterprise under the command of Christopher Pike, visits Rigel VII. While commanding the landing party, Pike enters an abandoned fortress and fights a Rigelian Kalar warrior. The landing party's ambush leads to seven injuries and three deaths, including Pike's yeoman. (TOS: "The Cage")
- The Enterprise, en route to Vega colony to hospitalize the Rigel VII victims, is diverted by an 18-year old distress call from the SS Columbia, crashed on Talos IV. (TOS: "The Cage")
- Ensign James T. Kirk is assigned with Lieutenant Commander Benjamin Finney to the USS Republic. (TOS: "Court Martial")
- While aboard the training vessel Republic during a change of watches, Ensign Kirk relieves Commander Finney and notes that a circuit, which should have been closed, to the atomic matter piles is opened. After closing the circuit, Kirk logs the incident. (TOS: "Court Martial")
- Commander Finney is reprimanded for the incident aboard the Republic. (TOS: "Court Martial")
- Leonard McCoy becomes romantically involved with the future Nancy Crater. (TOS: "The Man Trap")
- The Nexus crosses through the galaxy for the last time before claiming James T. Kirk, as well as nearly 400 El-Aurians.