“I’ll try to make my lies more opaque”: The Defector (TNG) vs. Duet (DS9)

A Romulan defector and a mysterious Cardassian show us what true patriotism might look like, in two fine examples of Star Trek at its Star Trek-iest.

“You’re on the other side now”: The Ensigns of Command (TNG) vs. Progress (DS9)

Data learns that honesty isn’t the best policy — until it is — and Kira learns that she doesn’t get to be the good guy anymore.

“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).

“The dream dreams the dreamer”: Birthright, Part 1 (TNG) vs. Tinker Tenor Doctor Spy (VOY)

Data learns to dream, and the Doctor learns to daydream.

“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.

“I’d like my death to count for something”: Yesterday’s Enterprise (TNG) vs. Year of Hell (VOY)

In these two stand-out episodes, we take a trip into two darker timelines … and get a glimpse of the very different TV shows that The Next Generation and Voyager could have been.

“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.

“Weird is part of the job”: Disaster (TNG) vs. Deadlock (VOY)

Disaster strikes, and we get to see how the crew of the Enterprise, and two identical crews of two identical Voyagers, cope in a crisis.