A Klingon tribunal, Narendra III, Rura Penthe ... the Star Trek universe is getting a bit smaller as the NX-01 finds itself in places that will later become familiar territory to Enterprise crews.

J.G. Hertzler has returned to his Klingon roots to guest star in "Judgment," the latest Enterprise episode to complete filming. Hertzler was General (and ultimately Chancellor) Martok in four seasons of Star Trek: Deep Space Nine. He was also a Vulcan Captain in the pilot "Emissary" and the Shapeshifter "Laas" in "Chimera" (both times credited under different names), and came back for Star Trek: Voyager as the Hirogen Hunter who trained Seven of Nine in "Tsunkatse."

Hertzler plays "Kolos," an aging and disenchanted Klingon advocate who is stuck with the task of representing Captain Archer before a tribunal, in much the same fashion Captain Kirk and Dr. McCoy stood trial in "Star Trek VI: The Undiscovered Country." Archer is accused of aiding an alien rebellion against the Klingon Empire, and if convicted, he could face a life sentence in the dilithium mines of Rura Penthe, or worse. Not only will there be several familiar references from previous Trek shows in this episode, but the story will give us a taste of the history of Klingon society through the 22nd century.

A new Klingon Tribunal Chamber set was constructed, to purposefully evoke the imagery and mood of the similar scene in "Star Trek VI" — the accused stands in the center on a platform underneath a bright, smoky spotlight; a Magistrate pounds a spherical gavel that makes sparks; a prosecutor and a defender walk the floor playing dramatically to their audience; and dozens of Klingons fill the rafters chanting, cheering, jeering and being generally rowdy. However, this set doesn't look exactly like the one from the movie, because rather than Kronos, this trial is taking place at the Klingon outpost on Narenda III (remember, from "Yesterday's Enterprise"?).

Other sets built for this episode, which concluded its seven-day schedule Monday, included a Klingon jail cell where Archer is held and where he meets privately with Kolos; the Bridge of a Klingon ship; and the Dilithium Mines of Rura Penthe, filled with piles and piles of rock salt to represent snow (the crew was warned to "wear old shoes" and "avoid contact with eyes" on that day). The standing ship sets were barely used in this episode except for the Bridge and Sickbay, and those scenes with the full principal cast were shot in less than a day and a half.

In post-production certain aspects of the Tribunal scenes will be digitally enhanced, and the visual effects team led by Dan Curry will also create landscape shots of Narenda III and Rura Penthe.

Other guest stars include John Vickery as "Prosecutor Orak"; Vickery previously played the Cardassian rebel "Gul Rusot" in DS9's seventh season, and also the Betazoid "Andrus Hagen" in Star Trek: The Next Generation's "Night Terrors." Daniel Riordan plays the Klingon captain who testifies against Archer, named "Duras" (no doubt an ancestor of the nefarious House of Duras in later centuries); Riordan was "Rondon" in TNG's "Coming of Age" and a Guard in DS9's "Progress."

The makeup and wardrobe teams had their hands quite full this time as nearly 20 Klingon extras at a time required their services, mainly for the Tribunal scenes. Also, for one day there was a group of alien refugees (the ones Archer gets in trouble for helping) called the Arin'Sen who needed a new look. For the Rura Penthe scenes, there were close to a dozen Klingon and other miscellaneous humanoid prisoners, along with Klingon guards, requiring makeup and costumes.

"Judgment" marks the return of director James L. Conway, a prolific Star Trek director whose last episode was the Enterprise pilot "Broken Bow." (Conway's DS9 two-parter "The Way of the Warrior" introduced us to Hertzler's Martok.) "Judgment" was written by consulting producer and staff writer David A. Goodman, from a story conceived by himself and Trek newcomer Taylor Elmore. The episode is tentatively scheduled to air March 26.