A strong lead performance can't save The Rhythm Section from molasses slow pacing. The Blake Lively revenge thriller showcases her excellent range, but not much else. An initially promising set-up is petered away in a mismanaged second act. Graphic action scenes provide a hint of excitement between the dull long stretches. They are not effectively used to further the narrative. This is an odd failure from producers Barbara Broccoli and Michael G. Wilson. The owners of the Bond franchise deliver a surprisingly boring film.

The Rhythm Section opens in London with Stephanie Patrick (Blake Lively) as a heroin addicted prostitute. Radiant flashbacks show a healthy, vibrant young woman with a loving family. She's visited by an investigative reporter (Raza Jaffrey) with startling news. The plane crash that killed her parents and siblings was not an accident. The plane was destroyed by a sophisticated explosive. The bomber walks the streets as a free man.

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Stephanie's drug addled odyssey to find the bomber leads to a reclusive former intelligence officer (Jude Law). He quickly beats the illusions out of her. She doesn't have what it takes to find the truth. But Stephanie has much more grit than expected. She enters the dark underworld of terrorists and killers. Her lost soul finding purpose in exacting revenge.

We've seen the weak and abused girl turned into a lethal killer countless times in cinema. It is a tired action trope that's rarely creative. The Rhythm Section doesn't break new ground, but differentiates itself on the strength of Blake Lively's performance. She's successful in portraying a strung out junkie. Her pale, emaciated, and bruised body covered with track marks; shaking from the agony of withdrawal. Her transformation into an able fighter builds anticipation. Which is deflated like a balloon with the film's sluggish plot. Lively takes more than a few lumps in physical fight scenes. She fully commits to the character. There just needed to be a better film around her.

The Rhythm Section is adapted from the novel by Mark Burnell, who also wrote the screenplay. I'm puzzled by the execution of the film. Are the pacing issues inherent to the source material? Or poor decision making from director Reed Morano (Billions, The Handmaid's Tale)? The film continually grinds to a crawl after fairly violent action. The downbeats become anchors. The hunt for the not so mysterious villain ends with a yawn. The Rhythm Section has a runtime of one hour and forty-nine minutes. It is badly in need of a shorter edit. You feel every second of the film from the halfway point.

The Rhythm Section falls flat, but has merit in its protagonist. Barbara Broccoli and Michael G. Wilson need to finance a redo with Blake Lively as this character. She has the dramatic and physical chops to take Stephanie Patrick further as an assassin. A sequel, in a more capable director's hands, would be worth seeing. The Rhythm Section is produced by Global Road Entertainment and Eon Productions with distribution by Paramount.

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