As the old saying goes, the truth is always stranger than fiction, and indeed there are some true stories so strange that they can’t be fully expressed with familiar modes of storytelling. Such is the case of “Rogue Agent,” a film that unfolds as a spy thriller and romantic drama before it takes a hard left into the seamy world of scam artistry.

For British viewers, the sordid story of Robert Freegard is likely well-known. The tale will even feel familiar for American viewers, thanks to the Netflix true crime series “The Puppet Master: Hunting the Ultimate Conman.” But the two projects take completely different tacks. Both start at the same point, when Freegard was passing himself off as an MI5 agent fighting the IRA from behind the bar of a Shropshire pub, “Rogue Agent” proceeds linearly from there, while “The Puppet Master” winds its way back and forth through Freegard’s life of coercion and control, achieving a far more eerie and chilling effect.

Directed by Declan Lawn and Adam Patterson, who directed the hit BBC series “The Salisbury Poisonings,” “Rogue Agent” is based on the article “Chasing Agent Freegard,” by Michael Bronner. Lawn and Patterson both worked on the screenplay, a clear telling of the events, focusing on one of the many victims Freegard left in his wake. The film itself is oddly paced and can’t quite land on a tone, flitting from spy film to rom-com to maudlin story of escape and empowerment.

Alice Archer (Gemma Arterton), a litigation solicitor, is a powerful businesswoman who falls in with Robert Freegard (James Norton), going by the surname Hansen, while he’s working, or posing, as a luxury car salesman. Alice is smart, running a background check on Robert, though her fears about his mysterious past are assuaged when he reveals he’s an MI5 spy. It’s a tale he’s spouted to a few college kids many years earlier, enlisting them as “freelance spies” in the fight against the Irish Republican Army, stringing them along for almost a decade in a sort of conspiratorial cosplay.

Alice’s intuition, as well as her private investigator, win out, but not after she’s started a business with him and made plans for the future. Robert discards her, knowing she’s onto him, and he takes what he can and splits for the next victim. But Alice decides to go after him, and the slow-burn thriller morphs into something that feels more like a Lifetime movie.

If “Rogue Agent” is at all compelling it’s due to Arterton, who has always easily held the screen. The screenplay doesn’t give her a lot to work with as a woman emerging from the fog of manipulation, gaslighting and betrayal, but she sells Alice’s devastation which hardens into determination.

It’s unfair to compare “Rogue Agent” to “The Puppet Master,” but it can’t be overstated that the flashback structure of “The Puppet Master” lent that docuseries a sense of sickening foreboding and unease throughout, as Freegard’s many acts of brainwashing and manipulation over the years unfold concurrently in the story. “Rogue Agent” is handicapped by the time limits of Bronner’s article, and a text epilogue only briefly mentions “further claims of fraud and deception,” a wild understatement, but Lawn and Patterson never experiment with timelines or story structure to build suspense. The meandering pace also saps the story of suspense and titillation.

In the saturated market of true crime content, a simple “woman in peril” tale isn’t enough to hold our interest anymore. Perhaps the prurient unravelings of Freegard’s greatest hits is best left to the nonfiction projects, but even with the liberties of narrative adaptation, Lawn and Patterson leave the psychological and emotional depths of this story unexplored. In her performance, Arterton extracts some truths as a woman scorned and searching for redemption, but the rest of “Rogue Agent” leaves one wanting, and searching, for more answers.

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‘ROGUE AGENT’

2 stars (out of 4)

No MPAA rating

Running time: 1:56

How to watch: In theaters and on AMC+ Friday

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