In brief: One or two good ideas surrounded by plenty of messy and/or bad ones. The Humpty Dumpty of time-travel shows.

A lot of "Shattered" plays like a flashback clip show, except the clips have been shot new instead of plundered from the film archive. We've got characters from probably half a dozen timelines popping up, with references to past shows thrown in for fun. It's like an assemblage of random episodes. Unfortunately, it doesn't serve a story so much as it serves a bland set of procedures.

It's like, hey, let's go through old scripts and throw ... this in. What's that? Why, it's a macrovirus. Do you remember the macroviruses from the episode "Macrocosm"? Unfortunately I do, but that's beside the point. There's so little actual substance here that the story spends a lot of its time borrowing material from other episodes. Meanwhile, we've got all these characters introduced from other timelines, past and future. This is bad for the forward flow of the story because every time we encounter a new set of characters we have to wait while the characters who already know what's going on stop and explain what's happening to those who don't. It grows tedious.

What's happening here is yet another take on "shattered time," something done plenty of times before in Trek, whether it was Voyager's "Relativity" or TNG's "All Good Things..." or "Timescape."

Of course, the first thing you'd better know going in is that this isn't science fiction, it's goofy science fantasy. The plot for "Shattered" does more than strain credulity; to say it pushes the envelope of believability -- even for a Trek time-manipulation premise -- is putting it mildly. We have the starship Voyager, which comes in contact with This Week's Random Spatial Anomaly, causing the ship to be divided into segments, where each of these segments exists in a different time frame, whether it's seven years ago, five years ago, today, or 17 years in the future.

The person at the mercy of this plot is Chakotay, who is the only crew member unaffected by the time manipulation's effects because of a "chronoton-infused serum" Doc concocted after Chakotay was zapped by the anomaly. This serum allows him to pass from section to section of the ship without his memory being affected; he simply passes through time to interact with whatever is happening in that part of the ship at that particular time.

I for one would like to know how the story accounts for location: Some of what happens takes place in the Alpha Quadrant, and the rest of it in various places scattered through the Delta Quadrant, so when Chakotay passes from one timeline to another, he also apparently moves tens of thousands of light-years. Is there some constant in time stories like this that ties location down to wherever the people involved need to be? Is Voyager here a mini-lab of timelines that exists in some finite location? I suppose the Timeline Gods have worked this all out, but never mind.

This makes no sense. Sure, when it comes down to it, no time-travel story makes any sense. This one just makes less sense than most. I'd also like to know why people who don't move through the timelines disappear when they cross from one area of the ship to another. If they're not moving through time like Chakotay, then where are they going?

Hey, I'm not asking for rock-solid science or logic here; I'm just asking that the story be entertaining. "Relativity" didn't make any sense either, but at least it broke free and won us over with its carefree lunacy. "Shattered," on the other hand, is a string of boring, only vaguely related scenes that segue uneasily into and out of one another. The plot is a flimsy excuse to move Chakotay in and out of timelines: He must move through Voyager and inject the ship's bio-neural gel packs with a dose of Doc's serum to bring the ship back to its normal temporal alignment (or whatever).

The key idea here, once the plot is fully under way, is that Chakotay recruits Janeway from the past -- from just before Voyager was pulled into the Delta Quadrant -- to help him put the ship back together. This means that past-Janeway will get a glimpse of bits and pieces of Voyager's fate over the next six-plus years, revealing the changes the Voyager crew has gone through since it was first pulled into the Delta Quadrant.

This isn't a bad idea at all, but it's not what the show is ultimately about, which plays more like a string of set pieces constructed around a convenient tech plot. There is, for example, an extended scene where Chakotay and Janeway end up in the "Captain Proton" holodeck program and the plot grinds to a halt. This scene isn't nearly as funny or useful as it wants to be, and plays more like a gratuitous rehash of "Bride of Chaotica!"

Other timeline events include: Seska's takeover of Voyager from "Basics, Part II"; a timeline set 17 years in the future, where Naomi Wildman and Icheb are grown adults; the present, where we witness the death of Tuvok; a period during "Caretaker" where B'Elanna blames Janeway for stranding them in the Delta Quadrant; and the time when Seven of Nine and the Borg assimilated the Voyager cargo bay in "Scorpion, Part II."

Other snippets include the aforementioned macrovirus and also a timeline where the crew is unconscious and dreaming, which Chakotay identifies as either the plot of "Waking Moments" or "Bliss." Your mission, if I hadn't already done it for you, was to identify the titles for these shows. (By the way, my usual griping about continuity doesn't mean random events thrown in to acknowledge that the writers did some homework are what make continuity worthwhile.)

The story becomes nearly as loony as "Relativity"; ultimately we have Seska trying to hijack Chakotay's efforts to bring the ship back into temporal alignment and then characters from half a dozen timelines charging in to the rescue, including a Maquis B'Elanna and a Borgified Seven of Nine.

The story makes much of the Temporal Prime Directive ("The less I know about the future, the better," says Janeway, who later presses Chakotay at every turn for more information about Voyager's fate), but it doesn't seem to make up its mind whether any of it matters. Chakotay resists telling Janeway anything about Voyager's future in the Delta Quadrant -- then moments later spills some beans, and then some more beans. But then the whole plan is to avert the anomaly's effect on Voyager in the first place, such that nobody's memory from any timeline will have been affected, so I must ask what the point is actually supposed to be.

I will try to answer that question by saying that the show makes an interesting point when Janeway witnesses Tuvok's death, prompting her brief vocal determination to prevent Voyager from ever being stranded in the Delta Quadrant. Chakotay talks her down from this with a reasonable speech about not undoing what's been done; changing everyone's future frankly isn't Janeway's job.

Then again, this is all to be moot anyway, since the timelines are to be reset to normal. I suppose the scene where Chakotay convinces Janeway there's more to Voyager's fate than the bad things she sees here exists just for the sake of discussion, albeit a good one.

The initial plot goal for "Shattered" is to break Voyager up into a bunch of disjointed parts. Of course, the script for "Shattered" is the very same thing -- a bunch of parts, with a strand running through it (the Janeway/Chakotay interaction) that can't break free of the illogical or arbitrary nature of tech plotting to be entirely successful. All the king's horses and all the king's men couldn't put this premise together again.

Next week: B'Elanna and Tom -- expecting a baby!

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