“Darkling” is episode eighteen of season three of Star Trek: Voyager.
Voyager – which appears to have now left the Nekrit Expanse – is in orbit around a planet. They are speaking to the Mikhal Travelers, a loosely governed race of explorers who extensively know the territory Voyager is entering and are willing to share. Captain Janeway is being told a story by a Traveler, Nakahn, about how they landed on a moon-sized creature when Kes comes over with another Traveler she introduces as Zahir, a pilot working with them. Zahir has been to the system Nakahn described recently and has never seen the beast in question. Voyager‘s crew are their guests and are giving them needed supplies. In exchange, Zahir says, they should tell them what’s true. A confrontation between Nakahn and Zahir results in Nakahn backing down. Afterwards, Zahir tells the captain the outposts are necessary evils. The asteroid field that Nakahn was talking about is rich in beryllium, though.
The Doctor and Neelix are on the holodeck, listening to Lord Byron and Gandhi arguing over matters when Kes joins them. This is part of the Doctor’s personality improvement program; he’s looking at historical figures and selecting the character elements he finds admirable to merge with his own program. So that he can improve himself. He could have used Kes’s assistance. Kes was busy on the planet. The Doctor considers the Travelers to be risk-taking thrill seekers. Bad news. He says this could be a reaction to Kes’s recent breakup with Neelix. This is the first time said breakup has been mentioned. Back in “Warlord”, Kes did tell Neelix she wanted some time apart. Given that, at the time, Kes was inhabited by another personality, it seemed that it was said personality saying this. It appears there was more to it than that. The Doctor’s advice to Kes is to repeat some of Gandhi’s; take a cold bath.
In sickbay, the Doctor is talking to B’Elanna. In his briefing to the away team, she was told that Klingons lacked an enzyme needed to metabolise the planet’s vegetation. It seems she had a salad. The Doctor is behaving a little oddly until B’Elanna tells him to back off. He apologises; he must have miscalculated and isolates the recent additions to his program. B’Elanna tells him he can’t just casually add behavioural subroutines as they have a way of interacting that is not always predictable. He should be careful. Or someone might hurt him. The Doctor realises he is currently stroking B’Elanna’s thigh and sees what she means. B’Elanna will take a look at his program later. The Doctor deactivates himself.
On the planet, Zahir and Kes are walking at night. When they kiss, someone is watching. Later, Kes beams back onboard Voyager, smiling. Tuvok sees her and says it’s three in the morning and she has an away team report due. She hadn’t forgotten. In sickbay, the Doctor is working on that report. He may not be a ship’s counselor, but he has enough psychological knowledge to be troubled by her behaviour. He would be remiss in not calling it to her attention. Kes tells him she’s 3 years old now and no longer a child.
Kes delivers the report to Captain Janeway in her ready room the next day. The captain realises Kes has been pulling an all-nighter; putting off an important task to the last minute then rushing through it. Something Janeway herself has done. Kes would like some personal advice; Zahir has invited her to spend some time with him. They could rendezvous with Voyager afterwards. Kes is a third of the way through her life and she is wondering if she wants to spend the rest of it on Voyager. She knows she’s changing and there are things she’s not satisfied with. The captain can help her weigh the pros and cons, but it’s Kes’s decision ultimately. They are in orbit for a couple more days, though.
Zahir is currently talking routes with Tuvok; he advises them to go off the direct course, or they will bump into the Tarkan, who are powerful and acquisitive and will take their ship. Tuvok and Zahir also talk about Kes, who then arrives. Later, Zahir is out at night when he hears something. Then a cloaked figure knocks him off a cliff. The figure returns to the outpost, where it’s revealed to be the Doctor. But he doesn’t look right. He also holds Nakahn’s hand to the fire, as he wants a ship and passage out of here.
Kes goes to sickbay and activates the Doctor – who looks normal again. Zahir has been found at the bottom of ravine, injured but alive. Tuvok is investigating. Before they can beam down to the outpost, though, B’Elanna arrives. She’s noticed a problem with the Doctor’s program. She explains that all the personalities he admired had dark threads running through them, and they are interacting in bad ways. Yes, this is an Evil Twin episode. The normal Doctor doesn’t know what’s happening. His Evil Twin knows about the Doctor, and is disgusted by him, and is plotting when he is deactivated.