In brief: Some good ideas in the midst of a derivative time-travel outing that ultimately can't transcend itself.

Multiple choice question: "E²" is a variation of which episode?

(A) DS9's "Children of Time"
(B) TNG's "Yesterday's Enterprise"
(C) TOS's "City on the Edge of Forever"
(D) Voyager's "Timeless"
(E) Two or three of the above
(F) All of the above
(G) Help! All time-travel stories look alike!

At this point in my Star Trek-viewing stage in life, I'm tempted to pick choice (G). While it's true that all the episodes on that list are memorable shows, I just can't do it anymore. I am about time-traveled out.

"E²" is an acceptable but all-too-familiar time-travel concept that writer Mike Sussman has woven reasonably well into the Xindi story arc. It has its moments, but it also has its share of tiresome action and derivative would-be revelations. In the end, it comes down to the fact that I have seen this story too many times over the years. It's old wine in a new bottle. Or maybe just the label on the bottle has been changed.

This episode also does not have the power of those aforementioned shows. The choice to be made in the end is not as demanding of our characters. And given the terrific past three installments of Enterprise, this is a step down. The previous three installments did not feel routine. This one did.

There's a lot here that's inspired by "Children of Time," which was a far superior episode because it was about our characters -- astonishingly and agonizingly -- choosing one destiny over another, and sacrificing a great deal in coming to that decision. (Only a brilliant last-minute twist, in the form of a character-based veto, spared them from that choice.) "E²," by contrast, is a more mechanically implemented storyline, because it involves choosing the best way to prevent, of course, the Destruction of Earth [TM]. It's less about sacrifice and more about playing the best odds.

The familiar story involves the Enterprise crew coming face-to-face with their own descendants, who helm a future version of the Enterprise (which I'll henceforth call the Enterprise-2 for sake of simplicity). The Enterprise is just about to travel through the subspace corridor to make their rendezvous with Degra when they are contacted by the Enterprise-2, whose captain tells them that traveling through the corridor will cause an accident that will send the Enterprise back in time 117 years. (In a nice touch, the Enterprise crew at first thinks that perhaps this other Starfleet vessel could be the NX-02, which we learn is named the Columbia.)

The captain of the Enterprise-2, a half-Vulcan named Lorian (David Andrews), explains the history of the Enterprise-2, which is the would-be destiny of the Enterprise. Stranded in the past, the ship would become a generational starship wandering the expanse for the next century, having cut itself off from contact with Earth, lest they contaminate the timeline and possibly prevent First Contact with the Vulcans from ever happening (which, by the way, is exactly the premise of Star Trek: First Contact). The mission was then passed down to the children and grandchildren and great-grandchildren: Stop the future Xindi attack(s) from ever happening. When they fail to stop the initial attack that kills 7 million, they must then prevent Archer's crew from becoming trapped in the past.

Confused? It's actually pretty straightforward and by-the-book as these things go, including, naturally, the built-in time paradox, which is all but mandatory. Certainly, this holds more water in a story sense than most of the arbitrary Temporal Cold War and the shenanigans of Crewman Daniels.

There are good things to be found in "E²." There's an inherently intriguing notion in the concept of a "generational starship" that must become a community unto itself, making alliances and recruiting crew members from other worlds. (Indeed, this is what one might've thought -- wrongly -- that Voyager would be all about.) And there's a certain appeal in seeing characters' reactions to personal details revealed about the future.

For instance, T'Pol learns -- in a conversation with her much older self, no less -- that she will have to forever cope with the emotions her Trellium-D experiment has unleashed, and that Trip will become an invaluable part of her life in that process. Meanwhile, Reed learns that he's doomed to a fate of permanent bachelorhood -- a future he immediately begins trying to rectify upon learning about it.

Still, a lot of this doesn't carry as much weight as it probably should've. The scenes involving Old T'Pol are pivotal, but unfortunately they are not particularly convincing; Blalock speaks too deliberately and does not capture the essence of a real character. (It's more like a parody of an old person.) And scenes of the crew discussing their futures seem too inconsequential, as if it were every day that you meet your descendants and find out how your life is (maybe) going to turn out. In a conversation between Travis and Hoshi, the deep conversation du jour is, "How about you? Did you get married?" (Would you really want to know?)

That question also surrounds Trip and T'Pol, who at the beginning of the episode are playing a low-key pursuit/rebuff game (he pursues, she rebuffs), providing the inevitable fallout from having had "sexual relations," as T'Pol so dryly puts it. The resulting banter is predictable. Later there's the (unsurprising) revelation that Lorian is the child of T'Pol and Trip, which forms the basis for some introspective dialog.

But the Enterprise-2 never really becomes a community that I felt for -- certainly not like the community in "Children of Time." This is mainly because of the mixed blessing of tying all this in with the Xindi arc. It's a concept that fits in well with the single-minded focus of this season, but suffers in part because of that focus. The Enterprise-2 looks not much like a generational community that has evolved for 117 years but like yet another of this season's points on which the fate of Planet Earth pivots. The story, by its nature, is too invested in the Xindi to care much about the people or lifestyles of the Enterprise-2.

The episode basically boils down to Lorian's dilemma and his resulting choices. You see, he had a chance to stop the initial Xindi weapon with a suicide run, but he hesitated for the briefest moment and missed his opportunity; 7 million on Earth died as a result. Lorian has agonized over this tactical error for months now, and is even more determined to make sure the mission to stop the second weapon is accomplished. What he fails to consider, however, is that stopping that first weapon would probably have only delayed an inevitable strike. (Indeed, without the initial attack, Earth might not have had a warning at all -- which of course begs that silly question again: Why did the Xindi send that "test" weapon in the first place? All it really accomplished was prompting the Enterprise's mission to stop them.)

Lorian's plan is to help the Enterprise make modifications that will prevent the time-shift from happening (I won't bother with the technobabble). But Lorian hides crucial facts about the odds of success, and Archer and Lorian find themselves in a heated disagreement, which ends with another example of Archer invoking his this-isn't-a-debate decree. (I'm tempted to ask: Whether he agrees or not, what's wrong with a discussion?) Old T'Pol has an alternate plan, but Lorian doesn't think it will work, and instead decides to steal equipment from the Enterprise to install on the Enterprise-2 so he can make the rendezvous with Degra himself.

Lorian's reasoning ("Billions of lives are at stake") contains an interesting irony, because it follows the same logic as the decision Archer made in stealing the warp coil from the innocent aliens in "Damage." This is an irony, alas, that seems lost on Archer, who is made out here as having the right answers. It might've been more interesting if he had the wrong answers. What we get here, while decent, is not challenging. Lorian's internal struggle to do what's best is commendable, but I really could've done without the tired sequence where the two Enterprises open fire on each other.

Similarly, the solution we ultimately arrive at -- both Enterprises working together to travel through the subspace corridor, with the Enterprise-2 fending off attacking aliens -- brings us to an action climax that strikes me as too routine and pat for this material. That we never find out exactly what happens to the Enterprise-2 in the midst of this chaos is probably a good thing, and allows the time paradox to resolve itself with a minimum of complications. But on the scale of time-travel shows, this can only emerge as average fare. It does not have the troubling questions of a classic Trek time-travel episode.

Perhaps the Xindi angle is simply too mechanical here to fully support a premise that demands more human feelings. To put it another way, it would probably be more interesting to meet your great-grandchildren if they weren't in such a hurry to go into battle alongside you.

Next week: The Council. 'Nuff said.

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