Entertainment

Dim ‘Lantern’

Geoffrey Rush gives voice to a monster amphibian (center) chatting with Ryan Reynolds. (Warner Bros. Pictures)

His face largely pasted on a computer-generated body, poor Ryan Reynolds acts only from the neck up in “Green Lantern,” a relentlessly silly superhero flick with eyeball-rolling dialogue — set in vast, familiar-looking digital realms that look like rejected models from the second “Star Wars” trilogy.

I actually bought issue No. 1 of “Green Lantern” as a 10-year-old and I’ve read up on the character’s convoluted history since then. But I still had trouble following his densely plotted, largely fun-free big-screen debut without a concordance.

There are several screens-full of mind-numbing exposition at the outset. Someone is invariably explaining something at great length when they aren’t stiffly proclaiming things such as: “Your words are compelling, young Earth Man” (even if they really aren’t).

The line is delivered by an animated amphibian voiced by Geoffrey Rush. He’s referring to Hal, a hot-shot test pilot played (from the neck up, anyway) by an uncomfortable-looking Reynolds, who appears like he’s ready for a fetish convention in his computer-generated costume.

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Hal’s been chosen for duty by a ring belonging to a dying extraterrestrial who was the greatest warrior among the Green Lanterns. Hal thus becomes the first human in a multispecies group protecting the universe under the guidance of a handful of wizened immortals. Got that?

Using a ring he has to periodically recharge with a lantern — and you thought your smartphone charger was cumbersome — our hero can carry out his duties by materializing anything he can imagine as weapons.

In practice, though, Hal is rather limited by the overly familiar concepts advanced by the movie’s four writers, who effectively turn “Green Lantern” into a sort of poor man’s “Iron Man” with corny special effects (presented in the usual eyeball straining 3-D).

Sinestro (Mark Strong), the head of the corps — whose heavily computer-generated appearance suggests that eyebrow shaping and tanning beds are popular pastimes at Green Lantern HQ — is skeptical that irresponsible Hal has the willpower necessary for the job.

But for reasons that remain as unconvincing as they are unclear, Hal is the only one of 3,600 Green Lanterns who can save Earth — and the universe — from Parallax, a boring CGI villain and erstwhile immortal who resembles a particularly bad case of California smog.

Since Green Lantern is basically computer-generated himself, it’s not exactly exciting watching him battle the smog creature, no matter how many chain saws and cannons he materializes.

Martin Campbell (“Casino Royale”) is a capable action director, but there isn’t really much to root for in a movie where everything and everyone is more or less blatantly fake. Some sequences — such as a helicopter crash thwarted by Green Lantern — are so confusingly edited it’s hard to figure out what’s going on.

Blake Lively doesn’t have a whole lot to do as Hal’s employer and occasional lover, who sometimes requires rescuing. No great loss; she and Reynolds have minus-zero chemistry.

Peter Sarsgaard (born in 1971) and Tim Robbins (1958) collect paychecks for chewing scenery as an amusingly unlikely son and father. Robbins is a fatuous US senator who arranges for his son, a balding biology professor, to conduct an autopsy on the dead E.T. — with truly unfortunate results for both of them. Fellow Oscar nominee Angela Bassett also avoids the unemployment line in some of these scenes.

“Green Lantern” gets so bogged down in the character’s arcane mythology that it makes surprisingly little use of Reynolds’ facility for light comedy. I couldn’t even figure out where the Earth scenes were supposed to be taking place (the press notes say the movie was shot in New Orleans).

“Let me prove to you our best days are not behind us,” Sinestro begs the immortals at one point.

If the immortals are worried about the overworked superhero genre — last month’s ridiculous “Thor” will be followed by next month’s “Captain America” — their concerns are probably well-placed, indeed.

lou.lumenick@nypost.com