If you haven’t seen “Legion” — the movie about angels declaring war on mankind — then Syfy’s new series “Dominion” will feel like a fever dream, with perhaps the most elaborate post-apocalyptic backstory ever. Yet even those familiar with the movie might find the 90-minute opener dizzying, as well as unevenly acted (to put matters kindly) and derivative in the extreme. Paired with returning planetary post-annihilation show “Defiance,” Syfy has an alliteration-friendly summer tandem for those inclined to watch overwrought melodrama. Anyone else should probably avoid this latest episodic invader as if it were the last show on Earth.

“Dominion” opens by informing viewers — via perhaps the most depressing on-air script ever — that 25 years ago, God disappeared, triggering an assault on Earth waged by angels under the leadership of the archangel Gabriel (Carl Beukes). Humans were able to repel them, we’re told, thanks in part to assistance from Gabriel’s winged peer Michael (Tom Wisdom), who has taken up residence in Vega (as in “Bright-light city gonna set my soul on fire”), one of the surviving outposts where people have congregated. (Stephen King’s “The Stand” also featured Vegas as a post-apocalyptic stronghold, which it can certainly feel like after a bad night at the tables. )

Vega, however, has its own elaborate political and caste systems, with brave soldier Alex (Christopher Egan) assigned to guard — while secretly bedding — the resident princess, Claire of the House Riesen (Roxanne McKee). One need not be a genius to anticipate that the relative peace vis-a-vis the evil angels won’t last, or that hushed talk of a mysterious chosen one destined to lead mankind against them will be advanced before premiere’s end.

Written by Vaun Wilmott and directed by Scott Stewart (reprising his role on “Legion”), the series — shot in South Africa and augmented by a lot of CGI — does feature some interesting players in supporting roles, including Alan Dale as Claire’s father and “Buffy the Vampire Slayer’s” Anthony Stewart Head as an unctuous elitist eager to expand his power.

The show musters a few ninth-inning wrinkles in an attempt to reel in viewers to subsequent episodes; by then, though, the dense mythology about the angel invasion, angel hierarchies and what’s transpired during the intervening quarter-century — along with scads of political jockeying seemingly lifted out of “Dune” — has come to feel almost oppressive. All in all, it provides scant incentive to endure another messianic “The Matrix” knockoff that (in success, anyway) will have to milk these stories across multiple seasons.

Even as a guilty pleasure, the series requires a willingness to suspend concerns about logic, and embrace the elaborate plot entirely on its own terms, ignoring the sizable gaps in coherence as the opener races through its setup.

Such gentle, undemanding souls are out there, no doubt. But for the rest of humankind, if this is as good as “Dominion” gets, Heaven help us.

TV Review: Syfy’s ‘Dominion’

(Series; Syfy, Thurs. June 19, 9 p.m.)

  • Production: Filmed in South Africa by Bold Films in association with Universal Cable Prods.
  • Crew: Executive producers, Vaun Wilmott, Scott Stewart, Michael Litvak, Todd Slavkin, Darren Swimmer, David Lancaster; producer, Jean Higgins; director, Stewart; writer, Wilmott; based on the movie “Legion,” written by Peter Schink, Stewart; camera, Adam Suschitzsky; production designer, Carlos Barbosa; editor, Henk Van Eeghen; music, Chris Young; casting, Zane/Pillsbury, Kate Dowd. 90 MIN.
  • Cast: Christopher Egan, Tom Wisdom, Roxanne McKee, Alan Dale, Anthony Stewart Head, Luke Allen-Gale, Shivani Ghai, Rosalind Halstead, Carl Beukes
  • Music By: