The production travails of FOX's "Terra Nova" have been chronicled so publicly and for so long that it's starting to feel like the show has been in development since the dinosaurs walked the earth. At one point, the series was going to debut at mid-season last year, then with a special two-night airing of the pilot episode in May, before finally being pushed to tonight at 8. There were issues with the weather on location in Australia, and the special effects process to create the show's prehistoric setting took longer than anticipated.

Along that long, complicated path, I've seen multiple versions of the "Terra Nova" pilot. Each time, the effects have gotten better, and the version of the dinosaurs you see tonight should look pretty darned spiffy.

But "Terra Nova" isn't just a time travel show where people are chased by dinosaurs; it's also a family drama. And as one of the show's many executive producers, Jon Cassar, put it to critics last month, "If you don’t tune in and love this family after the first hour, it doesn’t matter how good the dinosaurs look."

And the family remains much less interesting so far than the dinos - and, in fact, has gotten progressively less interesting with the tweaking.

The pilot begins in the next century, and earth is in the middle of a calamitous environmental disaster. The air is so toxic, the planet so overpopulated, that everyone has to wear rebreathers just to function, and they help only so much. But through scientists' discovery of a "time fracture," humanity now has a second chance, in which they'll send colonists back in time 85 million years to start civilization up from scratch.

(And before you start asking the inevitable questions about the butterfly effect, and what happens when a giant rock strikes the earth to wipe out all the dinosaurs, there's a technobabble-y scene about alternate timestreams to pre-empt them. Questions bad, cool dinos good. Got it?)

Among the families sent to colonize the Terra Nova settlement are the Shannons: cop Jim (Jason O'Mara), doctor Elisabeth (Shelley Conn) and kids Josh (Landon Liboiron), Maddy (Naomi Scott) and Zoe (Alana Mansour). They need to go back to the past for a variety of reasons, not least of which is that Zoe's birth was in violation of the 22nd century's strict population control laws.

(The first version of the pilot I saw made Zoe's existence into a very effective surprise at the end of a tense action sequence, but the writers went back and piled a bunch of clumsy expository scenes in front of that. Whatever the episode gains in clarity - which is less than I think it needed - it loses far more in entertainment.)

So the Shannons wind up in the past, where they have to deal with dinosaurs, with a mysterious splinter group of colonists known as "Sixers," with the colony's suspicious leader Nathaniel Taylor (Stephen Lang) and mostly with each other. And it's there that "Terra Nova" has its biggest issues.

Simply put, the Shannons are boring. Well, except for Josh, who gets to be annoying - the token rebellious teen whose function is to be stupid and get into trouble so there will be a story that week. I would suggest that the "Terra Nova" writers should know better - especially given how much fans of ABC's short-lived "V" despised that show's version of the same character - but then I remember that most of the key "Terra Nova" personnel (including lead producers Brannon Braga and Rene Echevarria) spent years on "24," where many a plotline was driven by the epic stupidity of Kim Bauer. (And before that, Braga ran various "Star Trek" spin-offs which were heavy on technobabble and light on characterization.)

O'Mara has a few moments of charm, mainly in showing Jim trying to reconnect with his kids after a long absence, but the Shannons overall are about the last reason I would recommend this show, after the cool visuals, some effective action set pieces and the expected strong supporting performance by Stephen Lang. (Though it seems easy to draw a line between Taylor and the gleefully genocidal soldier he played in "Avatar," Lang and the writers make enough distinctions that it's not just him playing the same guy in a slightly different exotic setting.)

That earlier version of the show I saw featured a more fractured Shannon marriage, in which Jim and Elisabeth had gone to Terra Nova in part to get a fresh start for their troubled union. They're all lovey-dovey now, and while I understand the producers' desire to give viewers a happy family to root for, nothing interesting has been added in place of the earlier tension.

If the Shannons were just there as a point of view device into this brave new/old world, and "Terra Nova" was designed to focus on its core strengths (dinosaurs chewing on humans and Stephen Lang chewing on scenery), that'd be okay. But everyone involved insists that they're the core, most important part of the series. And not only do they not work, but all the tinkering of the last year and a half has somehow made them work less than they did originally.

Alan Sepinwall may be reached at sepinwall@hitfix.com