The announcement that Jeri Ryan will be joining the cast of "Star Trek: Voyager" next season means the regular crew will increase by one - but only for a couple of episodes.

The arrival of Ryan, who will play a human who was "assimilated" by the evil Borg collective before being freed by Capt. Janeway and her crew, will come just before the departure of Jennifer Lien, who has played Kes since the series began three seasons ago.Lien will appear in this fall's season premiere - the conclusion of last spring's cliffhanger - but she and the character of Kes will be written out in the upcoming season's second episode.

"We have a wonderful story in which she's given a rather magical send-off, which does not say that she is totally absent forever," said executive producer Jeri Taylor rather cryptically.

(It begs the question - how can a starship racing across the galaxy toward home leave a character behind and have that character return at a later date? But stranger things have happened in the "Trek" universe.)

Taylor was quick to make it clear that the producers were not unhappy with Lien or her work.

"The reason why (she's leaving) has nothing to do with Jennifer Lien and her extraordinary abilities as an actress. It was simply a decision that we felt that the character was not working as well as we had wanted. That was our fault more than Jennifer's," Taylor said. "I think she will have a truly amazing career. She is beautiful and gifted and we were very sad to see her go."

While this is sort of the standard reply any producer gives when any actor is dropped from a show, there does seem to be more than a grain of truth behind it this time. In three seasons, the producers and writers of "Voyager" have never quite figured out what to do with the character of Kes.

All that stuff about Lien going on to a "truly amazing career" - that was Hollywood hyperbole, of course.

NEW CHARACTER: As much as the producers of "Star Trek: Voyager" struggled to define the character of Kes, they already seem excited about the new character Ryan will be portraying - dubbed Seven of Nine.

"She's the child that was raised by wolves," said executive producer Rick Berman. "She was taken at a very young age by the Borg and has very little recollection of her earlier human existence prior to the opening of this season."

For the uninitiated, the Borg are a race of drone-like cyborgs whose goal is to assimilate every race they encounter. They have a collective will and are completely without individuality.

(Except, of course, for the Borg queen who appeared in the last feature film, "Star Trek: First Contact.")

As to the decision to make the Borg a bigger part of "Voyager," that was a no-brainer.

"The Borg . . . are very popular. The audience loves them," Berman said. "And the idea of having someone whose life was stolen from them many years ago by the Borg and who now has to return to the human side was something we found fascinating. And the fact that it's seemingly one of the best-loved - or hated - villains that we've come up with in a long time made it seem to be a good mix."

And they're hoping that Seven of Nine fits into that mix well.

"She is a character who, during the course of the series, is going to be rediscovering and, in a way, redefining her humanity that's been ripped away from her so many years ago," Berman said. "And it's going to be the job of our cast and Janeway in particular to try to help bring back these human qualities that she once had."

The producers readily admit that, while this is a new character, it's not exactly a new twist for "Star Trek" to have a character exploring what it means to be human. Those have been around ever since the orig-inal series began three decades ago and have continued through "Next Generation," "Deep Space Nine" and "Voyager."

"I think among the very best elements of `Star Trek' since the original series has been characters that (`Trek' creator) Gene Roddenberry believed held a mirror up to humanity - serving as a way of us looking back at ourselves," Berman said. "Spock was like that in his half-human qualities. Data was designed specifically for that purpose. Odo, to some degree, and I think our doctor on `Voyager' to a great degree. Any time we can create a character that lets us reflect or comment on humanity, it does nothing but help the show."

The addition of Seven of Nine is also intended to shake things up on the Voyager a bit.

"She is just so strong and focused, and she looks Janeway right in the eye and gives as good as she gets," Taylor said. "So we are predicting a lot of excitement and buoyancy and a lot of things for the Voyager crew to grapple with in terms of this new person in their midst."

As for Ryan, she got a taste of TV science fiction on the ill-fated NBC series "Dark Skies" last season. But that really didn't prepare her to play a freed Borg.

"She's very different, obviously, from anything else I've played because she doesn't start out human," Ry-an said."So it's fun. It's certainly a learning process for me trying to figure out exactly who she is as we go along and to figure out the arc of the character as she learns to become human again."

Of course, seeing herself under all of that Borg makeup was a bit of a shock.

"My first thought was, `Why did I want to be an actress again?' " Ryan said. "It's rather surreal."

THE WRATH OF FANS: Brannon Braga, co-executive producer of "Voyager," has learned just how obsessed some Trekkers (or is that Trekkies?) can be.

He has made no secret of the fact that, when he became a writer on "Next Generation," he had never seen an episode of the original "Star Trek." He still hasn't.

And, as the primary writer of the last two theatrical movies - "Generations" and "First Contact," he has angered some of those fans. And those fans have suggested on the Internet that there's something serious-ly wrong with Braga.

That included a series of attacks against him on the Internet along the lines of "How dare I kill Kirk when I'd never seen the original series. That kind of thing," Braga said.

"I don't know how I got targeted. I think to a degree I fostered that myself because I became a little iconoclastic toward the fans. Some of their questions are so picayune, and some of their attacks against the show I think are unfair."

He admits he made a "disparaging remark" about the fans. "And it circulated very quickly. And on the Internet in particular, fans took up an `Is Brannon Braga evil?' message board," Braga said. "It had nothing to do with the show. It had to do with me."

Not that he's all that worried about it.

"It has died down," Braga said. "And it's such a small set. I mean, it's a small population that was doing it."

And, perhaps causing himself a bit of trouble, Ethan Phillips, who plays Neelix on "Voyager," took up Braga's case.

"It's interesting, though, that fans can crush you," Phillips said. "They can squeeze you. They can diminish you. But if you say one thing about the fans, then you're evil."

And Braga is neither anti-fan nor anti-obsessed fan.

"My thought is - better obsessive interest than no interest at all," he said.

DON'T HOLD YOUR BREATH: There's a certain contingent of Trekkers out there who want to see the relationship between Capt. Janeway (Kate Mulgrew) and her first officer, Chakotay (Robert Beltran) heat up. Get physical.

It's not something the producers are planning anytime soon. Nor is it something that Mulgrew is in a hurry to see, either.

"I am the captain of this ship, and it's bad enough that I got us all lost in space, right?" Mulgrew said. "I think that for Janeway to be running on the bridge and screaming `Red alert!' and disappearing into her ready room with Ixnay (Chakotay) over here every five minutes is not a positive thing.

"Her dedication and her commitment is to the crew. What I'd love to see and what I think is happening is that they're going to have - for the first time in the history of prime-time television - a relationship that transcends the obvious. It is going to be full of that complexity, that depth, that love and that tenderness without dropping through."