“The Great Balance is a lie”: A Taste of Armageddon (Original Series) vs. The Sound of Thunder (Discovery)

Prime Directive? What Prime Directive? Kirk and Saru each take the law into their own hands.

“Up north, quite a ways”: Spectre of the Gun (Original Series) vs. North Star (Enterprise)

Kirk and Archer take their respective Enterprises into the Wild, Wild West … but, you know, in space.

“Did humans really talk like that?”: A Piece of the Action (TOS) vs. The Royale (TNG)

Away teams from two Enterprises encounter echoes of Earth’s past on far-off planets … and also cheat at craps (and fizzbin).

“I’m literally angry with rage!”: The Squire of Gothos (TOS) vs. Where No Fan Has Gone Before (Futurama)

The crew of the Enterprise meet Earth’s biggest fan, and the cast of the show meet Star Trek’s biggest fan.

“There’s coffee in that nebula”: The Corbomite Maneuver (TOS) vs. The Cloud (VOY)

Kirk and Janeway put their morals where their mouths are, risking ship and crew to show that the Federation’s values aren’t just words.

“What are you, that you could do this?”: The Enterprise Incident (TOS) vs. Face of the Enemy (TNG)

Troi and Kirk try on Romulan faces, and oppression and espionage test what Troi and Spock are capable of.

“There’s got to be something better than this”: Mirror, Mirror (TOS) vs. Crossover (DS9)

In Trek vs. Trek’s first trip to the Mirror Universe, we see how differently the Original Series and Deep Space Nine approach the idea of ‘the darkest timeline’.

“I feel angry, but I want to love”: Journey to Babel (TOS) vs. Sarek (TNG) vs. Lethe (DSC)

Spock and Burnham have daddy issues, and Sarek is emotionally exhausted from appearing in 3 different series of Star Trek.