Mr. Spock remains the character most closely identified with Star Trek, even more than Captain Kirk. As Kirk's stalwart right hand, he was often by his side during the events of The Original Series and just as often in command of the Enterprise at times when Kirk was incapacitated. By the events of Star Trek II: The Wrath of Khan, Spock had become a captain in his own right and opened that film in the midst of training a crew of cadets. But as to how many times he took command of the Enterprise, that's a surprisingly tricky question to answer.

By the time Star Trek: The Next Generation arrived, the dynamic between a captain and their "Number One" was more codified. Captain Picard, for instance, would often spend long periods away from the Enterprise on missions. In contrast, Kirk rarely went further than the planet the ship was orbiting at the time and often remained in command even though Spock controlled the ship from the bridge. As such, the following list represents all the times Spock formally took command of the Enterprise during The Original Series. They are arranged in chronological order by season.

Season 1

Episode 7, "What Are Little Girls Made Of?"Captain Kirk and Christine Chapel beam down to the surface of Exo III, where Chapel's former fiancé has been studying ancient machines that can create androids. Kirk is cut off from the ship and kept in the complex as a prisoner, where an android duplicate is made of him. The duplicate returns to the Enterprise in Kirk's place and snaps at Spock -- thinking that he's imitating the real captain -- which raises the Vulcan's suspicions. When the false Kirk returns to the planet, Spock follows with a security team to rescue the real captain.

Episode 9, "Dagger of the Mind."When Kirk beams down to a penal colony after a seemingly crazed stowaway hides out aboard the Enterprise. Spock stays behind in command of the ship, where he conducts a mind meld on the stowaway. Kirk is subjected to a mind-altering device on the planet's surface but fights it off long enough to direct a fellow Starfleet officer, Dr. Helen Noel, to deactivate the force field surrounding the facility. As with "What are Little Girls Made Of?" Spock then beams down with a security team.

Episode 11, "The Menagerie, Part 1." "The Menagerie" was a repackaged version of the original Star Trek pilot "The Cage." Until the latter episode's video release in 1986, it was the only way to see "The Cage." The framing device entails Spock hijacking the Enterprise and taking a now-paralyzed Captain Pike back to Talos IV where he can join Vina in the Talosians' gilded cage. Kirk is left behind but catches up with the Enterprise, and Spock is put on trial for mutiny. During the trial, he shows footage from Pike's first visit to Talos IV -- the events of "The Cage" -- as part of his defense.

Episode 17, "The Squire of Gothos."Trelane, a seemingly omnipotent being with a penchant for 19th-century chivalry, kidnaps Kirk and several other crew members for his amusement. Spock takes command of the Enterprise and leads the search for them. He deduces the captain's location and arranges for the lost crew members to beam up. Kirk retakes command just as Trelane elevates his threats to keep his "pets" from running away.

Episode 18, "Arena."One of The Original Series signature episodes finds the Enterprise pitted against a Gorn ship after an attack on a Federation colony. Advanced aliens intervene in the battle and set Kirk and the Gorn captain upon an uninhabited planet to fight to the death. Spock remains in command of the Enterprise. He and the rest of the crew are helpless to do anything but watch, but the Vulcan successfully deduces Kirk's checkmate move: constructing a crude firearm after assembling the chemical components of gunpowder.

Episode 19, "Tomorrow Is Yesterday."The Enterprise is flung back in time and arrives on Earth in the year 1969. Kirk and Sulu beam into a U.S. military base in order to remove evidence of the ship's presence in the past. The captain is eventually captured and interrogated. Spock, meanwhile, maintains command of the Enterprise, and devices a rescue plan as well as a means of restoring the timeline and returning the ship to the 23rd Century. He ultimately beams down to the planet's surface and frees Captain Kirk.

Episode 20, "Court Martial." Kirk is subjected to a court-martial following the death of a crewman during an ion storm. While he stands trial for his life, Spock uses a game of 3-D chess to deduce that the ship's computer records have been tampered with, casting doubt on the evidence against his captain. The two conspire to unearth the truth: the supposedly dead crew member is actually alive and well.

Star Trek Spock Scotty

Season 2

Episode 2, "Who Mourns for Adonais?"A being claiming to be the god Apollo holds the ship captive, then insists that Kirk and his officers beam down. Spock is forbidden -- Apollo claims he too closely resembles Pan -- and while the landing party bargains with the god, the Vulcan works to pinpoint his power source and disable it. He eventually deduces that Apollo's temple is the source of his abilities and destroys it with phasers: freeing the crew and causing Apollo to mournfully revert to nothingness.

Episode 4, "Mirror, Mirror." This episode marks the origin of Star Trek's Mirror Universe, as Kirk, McCoy, Uhura and Scotty are sent to the dark parallel "Terran Empire" during a transporter accident. Spock, alerted to what has happened, apprehends the manic, agitated Mirror Universe counterparts of Kirk and the away team, escorting them to the brig.

Episode 6, "The Doomsday Machine."Kirk beams over to the wreck of a Federation ship, the Constellation, which has been disabled by what turns out to be a "planet-killing" weapon. He remains on board the Enterprise when the planet killer attacks, while Kirk stays aboard the Constellation. The other ship's agitated commander, Commodore Decker, relieves Spock of command and proceeds to get the Enterprise caught in the colossal machine's tractor beam. Kirk and the away team bring the Constellation back online in time for him to drive it into the core of the machine and destroy it.

Episode 16, "The Gamesters of Triskelion."Kirk, Uhura, and Chekov are abducted by alien "Providers" -- essentially glowing brains in jars -- and restrained with shock collars while being trained to fight for their abductors' amusement. Spock, left behind in the Enterprise, is able to track the captain's location and arrives in orbit around the planet to rescue him.

Star Trek Spock McCoy Uhura

Season 3

Episode 2, "The Enterprise Incident." A seemingly irrational Kirk takes the Enterprise into the Neutral Zone, where it is soon surrounded by Romulans. Kirk and Spock beam to the enemy ship to discuss terms of surrender, only for Spock to seemingly turn on his captain: accusing him of acting without orders. Appearing to collude with their foes, Spock applies the Vulcan nerve pinch to Kirk -- apparently killing him -- then beams back to the Enterprise to take command. It's all a ruse: Kirk and Spock have been ordered to steal a cloaking device. Spock ostensibly remains in command while Kirk returns to the enemy ship disguised as a Romulan.

Episode 3, "The Paradise Syndrome."Spock is forced to abandon an amnesiac Kirk near an alien obelisk on a pre-warp planet to deflect an oncoming asteroid. The planet's inhabitants believe Kirk is a god, a situation that gets out of hand as Spock and the Enterprise try and fail multiple times to stop the asteroid. As the ship races back toward the planet, Spock realizes that the symbols on the obelisk may hold the key to defeating the threat. When they arrive, he beams down to the planet's surface, restores Kirk's memory with a mind meld and assists the captain in activating the obelisk to divert the asteroid.

Episode 9, "The Tholian Web."Kirk seems to disappear from a "dead" Federation ship, the Defiant, while the Tholians arrive and demand that the Enterprise immediately departs from their territory. When the Defiant fails to materialize, Spock declares the captain dead, and must first deal with the Tholians and then -- upon realizing that Kirkis alive -- devise a means of restoring him from his incorporeal state.

Episode 16, "The Mark of Gideon." The elimination of disease and aging leads the planet Gideon to a catastrophic overpopulation problem. They plan to solve it by introducing Kirk to their germ-free environment and letting him become "patient zero:" eliminating their excess numbers through disease. Their ruse involves a lengthy stint onboard a replica of the Enterprise, while Spock negotiates with the Gideons aboard the actual Enterprise.

Episode 17, "That Which Survives."Kirk and the away team are stranded on an alien planet while an ancient booby trap hurls the Enterprise almost 1,000 light-years away. Spock orders the ship back to the planet, but engine sabotage requires that he and Scotty puzzle out a means of slowing the ship to safe speeds. Once they do, they return to the planet and safely retrieve the captain.

KEEP READING: Star Trek: Why Chateau Picard Changed After The Next Generation