The BEST episodes of Star Trek season 2

Every episode of Star Trek season 2, ranked from best to worst by thousands of votes from fans of the show. The best episodes of Star Trek season 2!

Space. The Final Frontier. The U.S.S. Enterprise embarks on a five year mission to explore the galaxy. The Enterprise is under the command of Captain James T. Kirk, who is assisted by First Officer Mr. Spock, from the planet Vulcan, and Chief Medical Officer Dr. Leonard 'Bones' McCoy. With a determined crew, the Enterprise encounters Klingons, Romulans, time paradoxes, tribbles and genetic supermen led by Khan Noonien Singh. Their mission: to explore strange new worlds, to seek new life and new civilizations, to boldly go where no man has gone before.

Last Updated: 10/11/2025Network: NBCStatus: Ended
The Trouble with Tribbles
star
7.94
1075 votes

#1 - The Trouble with Tribbles

Season 2 - Episode 15 - Aired 12/29/1967

Kirk must defuse a Klingon scheme to destroy a grain shipment... and cope with a seemingly benign creature known as a tribble, which reproduces at amazing speed.

Directors: Joseph Pevney
Watch Now:Amazon
Mirror, Mirror
star
7.84
1230 votes

#2 - Mirror, Mirror

Season 2 - Episode 4 - Aired 10/6/1967

Kirk and three of his officers are accidentally transported into a parallel "mirror" universe where violence, greed, and evil are commonplace.

Directors: Marc Daniels
Writer: Jerome Bixby
Watch Now:Amazon
Amok Time
star
7.83
1233 votes

#3 - Amok Time

Season 2 - Episode 1 - Aired 9/15/1967

Spock must go to Vulcan in order to perform the Vulcan mating ritual.

Directors: Joseph Pevney
Watch Now:Amazon
Journey to Babel
star
7.72
911 votes

#4 - Journey to Babel

Season 2 - Episode 10 - Aired 11/17/1967

Spock meets his estranged father when the Enterprise escorts a group of ambassadors to a conference on the planet Babel.

Directors: Joseph Pevney
Writer: D.C. Fontana
Watch Now:Amazon
The Ultimate Computer
star
7.65
997 votes

#5 - The Ultimate Computer

Season 2 - Episode 24 - Aired 3/8/1968

The Enterprise is used to test a new super-sophisticated computer, but it soon develops a mind of its own.

Writer: D.C. Fontana
Watch Now:Amazon
The Doomsday Machine
star
7.65
1258 votes

#6 - The Doomsday Machine

Season 2 - Episode 6 - Aired 10/20/1967

The Enterprise must stop an ancient doomsday weapon that is capable of destroying entire worlds... and has already totalled one Constellation-class cruiser.

Directors: Marc Daniels
Watch Now:Amazon
The Changeling
star
7.41
1227 votes

#7 - The Changeling

Season 2 - Episode 3 - Aired 9/29/1967

The Enterprise encounters an ancient Earth probe bent on the sterilization of all life.

Directors: Marc Daniels
Watch Now:Amazon
Assignment: Earth
star
7.33
934 votes

#8 - Assignment: Earth

Season 2 - Episode 26 - Aired 3/29/1968

The Enterprise is sent on a mission back to Earth in the year 1968, where the crew encounters the mysterious Gary Seven, who claims to have been sent by advanced beings to save the planet.

Writer: Art Wallace
Watch Now:Amazon
I, Mudd
star
7.28
927 votes

#9 - I, Mudd

Season 2 - Episode 8 - Aired 11/3/1967

The Enterprise is taken over by a group of androids who are working for Kirk's old nemesis, Harry Mudd.

Directors: Marc Daniels
A Piece of the Action
star
7.17
906 votes

#10 - A Piece of the Action

Season 2 - Episode 17 - Aired 1/12/1968

The Enterprise travels to a planet suffering from cultural contamination from an earlier expedition - the inhabitants mimic the culture of 1930's gangland Chicago.

The Deadly Years
star
7.14
996 votes

#11 - The Deadly Years

Season 2 - Episode 12 - Aired 12/8/1967

A landing party, including the command staff, are infected with a disease that causes rapid aging and senility.

Directors: Joseph Pevney
Watch Now:Apple TV
Obsession
star
7.11
903 votes

#12 - Obsession

Season 2 - Episode 13 - Aired 12/15/1967

The Enterprise must deal with a creature from Kirk's past that feeds on human blood.

Directors: Ralph Senensky
Writer: Art Wallace
By Any Other Name
star
7.08
758 votes

#13 - By Any Other Name

Season 2 - Episode 22 - Aired 2/23/1968

The Enterprise's command crew must thwart an invasion by aliens from another galaxy who plan to conquer this one.

Who Mourns for Adonais?
star
7.05
1023 votes

#14 - Who Mourns for Adonais?

Season 2 - Episode 2 - Aired 9/22/1967

The Enterprise encounters an alien who claims to be the Greek god Apollo.

Patterns of Force
star
7.02
835 votes

#15 - Patterns of Force

Season 2 - Episode 21 - Aired 2/16/1968

The Enterprise seek out a historical researcher and discover he has contaminated a culture, rendering it into a near-duplicate of Nazi Germany.

Directors: Vincent McEveety
Return to Tomorrow
star
6.97
829 votes

#16 - Return to Tomorrow

Season 2 - Episode 20 - Aired 2/9/1968

The Enterprise discovers three discorporeal intelligences who seek their help in gaining physical bodies... but one of them has plans of his own.

Friday's Child
star
6.96
921 votes

#17 - Friday's Child

Season 2 - Episode 11 - Aired 12/1/1967

Kirk, Spock, and McCoy land on a primitive planet to negotiate a mining treaty, but soon find themselves involved with intrigue and must flee with a pregnant woman into the surrounding mountains.

Directors: Joseph Pevney
Writer: D.C. Fontana
The Immunity Syndrome
star
6.95
759 votes

#18 - The Immunity Syndrome

Season 2 - Episode 18 - Aired 1/19/1968

The Enterprise must destroy an enormous space amoeba before it reproduces and threatens known space.

Directors: Joseph Pevney
Wolf in the Fold
star
6.75
957 votes

#19 - Wolf in the Fold

Season 2 - Episode 14 - Aired 12/22/1967

A serial killer stalks a planet... and Scotty is the prime suspect.

Directors: Joseph Pevney
Writer: Robert Bloch
Metamorphosis
star
6.75
947 votes

#20 - Metamorphosis

Season 2 - Episode 9 - Aired 11/10/1967

When their shuttle is diverted to a planetoid, Kirk meets one of the pioneers of space flight, Zefram Cochrane.

Directors: Ralph Senensky
Writer: Gene L. Coon
The Gamesters of Triskelion
star
6.67
920 votes

#21 - The Gamesters of Triskelion

Season 2 - Episode 16 - Aired 1/5/1968

Kirk, Chekov, and Uhura are kidnapped and forced to participate in a series of gladiatorial games.

Directors: Gene Nelson
The Apple
star
6.65
942 votes

#22 - The Apple

Season 2 - Episode 5 - Aired 10/13/1967

Kirk attempts to assist a primitive people that are ruled over by a computer named Vaal.

Catspaw
star
6.60
993 votes

#23 - Catspaw

Season 2 - Episode 7 - Aired 10/27/1967

When a landing party disappears and one man is beamed up dead, Kirk and Spock investigate and meet a pair of aliens who seem capable of performing magic.

Directors: Joseph Pevney
Writer: Robert Bloch
Bread and Circuses
star
6.59
775 votes

#24 - Bread and Circuses

Season 2 - Episode 25 - Aired 3/15/1968

The Enterprise investigates the disappearance of a merchant ship crew on a planet ruled by a twentieth-century incarnation of ancient Rome.

A Private Little War
star
6.50
798 votes

#25 - A Private Little War

Season 2 - Episode 19 - Aired 2/2/1968

Kirk becomes involved in an arms race when the Klingons equip a native people with superior weaponry.