“What could possibly go wrong?”: A Fistful of Datas (TNG) vs. Our Man Bashir (DS9)

Worf and Troi play Red Dead Redemption, while Bashir and Garak play Goldeneye.

“We’ve got a long way to go”: Eye of the Needle (Voyager) vs. The Sound of Her Voice (DS9)

The crew of Voyager come to terms with being stranded in the Delta Quadrant, and the crew of Deep Space Nine “shouldn’t have to mourn alone”.

“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.

“A little ship that took a little trip”: The Terratin Incident (TAS) vs. One Little Ship (DS9)

Honey, I Shrunk the Crew of the Enterprise (and a Runabout)

“This feels like a reckoning”: Shattered Mirror (DS9) vs. Vaulting Ambition (DSC)

The Siskos and Burnham spend more creepy quality time with the Mirror versions of their lost loved ones, which turns into a sitcom for the Siskos, and a horror movie for Burnham.

“Every moment is a test”: Through the Looking Glass (DS9) vs. The Wolf Inside (DSC)

Sisko and Burnham impersonate their Mirror Universe selves, which leads Burnham to question her faith in herself and in humanity … and leads Sisko to look cool dual-wielding phasers.

“It is you who are not real, sir”: The Big Goodbye (TNG) vs. Badda-Bing, Badda-Bang (DS9)

An early episode of The Next Generation starts a Trek tradition of holodeck malfunctions, while a late-series episode of Deep Space 9 lets the crew use the holodeck exactly as its designers probably intended: to pull holographic casino heists.

“You’re too late, we’re everywhere”: The Adversary (DS9) vs. State of Flux (VOY)

Suspicion and paranoia abound on the Defiant and the Voyager, as shape-shifting impostors and surgically altered spies force Sisko and Chakotay to question how much they can trust those under their command.

“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’.