The success of the "Harry Potter," "Twilight" and "The Hunger Games" film series has brought on wave after wave of adaptations that hope to tap into that lucrative young-adult market. And so, it was only a matter of time before one of these aspiring franchises sucked in Chloe Grace Moretz, who broke through as the tough-as-nails Hit-Girl in 2010's "Kick-Ass."

Regrettably, however, her turn in the adaptation of Rick Yancey's "The 5th Wave" is too little, too late, and too lame.

Moretz stars as Cassie Sullivan, a Solo cup-swigging Ohio teen whose biggest worry was trying to impress her crush, Ben Parish (Nick Robinson). But that was before the arrival of The Others, an extraterrestrial threat that hovered above the Earth in a ship straight out of "Independence Day," sending out waves of attacks that wiped out our power, caused coast-crushing tidal waves and fueled widespread plague.

With each wave, Cassie experienced loss, first her school, then her home, then her parents. But even as The Others move among mankind in human form, Cassie is dedicated to reclaiming her litter brother Sam (Zackary Arthur), whatever the cost.

"The 5th Wave" has a promising premise, that is until it folds in a second story, following an orphaned Ben through a boot camp that turns pint-sized survivors into child soldiers. This too is an intriguing place to launch a story, but two hours isn't enough time to successfully tell both, and so both suffer. In Cassie's storyline, she bravely quests through a brutal post-apocalyptic landscape that's all the more terrifying because there's no fantastical elements to make this seem like some far-off future. But she's a flailing Final Girl: Falling down ravines, stumbling through deserted highways littered with corpses, and blindly running toward the Army base where Sam is stationed, she makes no plan along the way, which makes her more infuriating than engaging. And Moretz doesn't help.

The starlet who once made us cheer with her sassy smirk and mirthful mastery of fight choreography sleepwalks through "The 5th Wave." Most of her lines, including a smothering voiceover laced throughout, are delivered in a groggy monotone. Others are punctuated by wide eyes and a trembling lip. Yet Moretz manages nothing resembling heartfelt emotion. And things go from blah to blech as the requisite second love interest enters the picture. I mean, we can't target a dystopian movie at girls without a love triangle, right?

Awaking in a lovely farmhouse, Cassie meets Evan Walker (Alex Roe), who's tall, handsome and has apparently saved her life. Although there are signs she shouldn't trust him, what choice does Cassie have? She's alone in a world made strange by an invisible threat. Their intriguing uneasy alliance becomes a downright queasy romance as Evan woos Cassie while tending to her wound, leading to a climactic twist that's as predictable as it is problematic. Yet it's not even the movie's most groan-inducing gambit. That'd be the "twist" at the tail-end of Ben's thread. And really, if you think about it for a second, you can probably guess what secret is uncovered in the military base.

Considering Moretz seems to have lost her star power amid the waves, I was grateful for any return to Ben's plotline. Hardened by the deaths of his family, he's earned the nickname Zombie. However, Robinson shows more genuine pain and compassion than Moretz ever musters. Proud and protective of his new family, Zombie runs his squad with a stern hand but a warm heart. Yet because we just have to get back to Evan and Cassie making out in the woods, director J Blakeson never bothers to invest much time in the squad's characters, like Tony Revolori's bespectacled Dumbo or Talitha Bateman's fiesty Teacup. Sure, the rogue Ringer (Maika Monroe) gets some sneering zingers, but the rest of the crew hardly gets a line or a name before their lives are put in peril by a suicide mission. Robinson's earnestness and his chemistry with Monroe offer some bright spots amid "The 5th Wave's" washes of doom and gloom, but there's little that's worthwhile beyond that.

Blakeson's action sequences lack punch, constructed without a sense of drive or geography. The pacing is deadly, and gives no concept to how much time has passed. The "love" subplot sours as Moretz and Roe go together as well as peanut butter and gasoline. And the film's attempt at teen speak offers such gems as "She looks like she's funny." "Yeah. Actually, she's really funny."

Perhaps most frustrating of all is that the film has pulled together young actors who've won acclaim elsewhere (Robinson's "The Kings of Summer," Monroe's "It Follows," Revolori's "Grand Budapest Hotel"), yet fails to showcase them, wasting their talents as it did my patience. Instead, we get Moretz droning on about humanity and hope, while "The 5th Wave" rides along without character or reason to care.

"The 5th Wave" opens today nationwide.