Star Trek revisits iconic 58-year-old episode and brings back mysterious species for Strange New Worlds

Terrarium pays homage to the classic Star Trek story Arena, and sees Erica Ortegas (Melissa Navia) stranded on a desolate planet on the other side of a wormhole, with the Enterprise losing contact with her.

While there, she's saved by a Gorn (Warren Scherer) who she befriends and manages to communicate with by means of a translation device. But, by the end of the episode, Ortegas's feeling of being watched proves to be true when it's revealed that the whole situation has been an experiment by the Metrons.

The Metron (Dariush Zadeh) appears to Ortegas and tells her: "Humans and Gorn, two barbaric species determined to destroy the other. But what could happen if you were forced together with a need to survive? We found the idea of such an experiment intriguing."

It also reveals that the Gorn didn't need Ortegas to survive, but it instead befriended her because it was lonely. Similarly, Ortegas was able to see past her pain and trauma. It adds: "There is hope for your two species."

If all of this sounds familiar, that's because it is. It bears a huge amount of similarities to 1967 episode Arena, which introduced the Metrons and sees them force Captain Kirk (William Shatner) to battle an opposing Gorn captain. Terrarium now marks the first time since 1967 that the Metrons have been seen on screen (although they were mentioned in Discovery).

Of course, Terrarium also has some notable differences from Arena. In Terrarium, Ortegas and the Gorn join forces in an attempt to escape the planet (although the Gorn is ultimately killed by La'an before Ortegas can stop her). In Arena, Kirk and the Gorn are embroiled in a battle, a moment that has gone down in Star Trek history (although Kirk stops short of killing the Gorn Captain and refuses to destroy the ship).

Crucially, Terrarium also sets up events to come in future Star Trek episodes by saying: "We need more data to determine whether the humans and the Gorn will ever find peace." It also sees Ortegas's memory wiped (thus meaning she can't warn Kirk of what's to come when he encounters the Metrons later on).

Already this season, we've seen revelations about Spock and a return from iconic characters Q and Trelane, plus a Doctor Who crossover for fans of both franchises.

But, with the finale episode still to come, it's clear we're not finished with the Gorn as Marie Batel's (Melanie Scrofano) fate hangs in the balance after being infected with Gorn DNA.

Buckle in!

Star Trek: Strange New Worlds is available to stream on Paramount+.

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