SAS: Red Notice promises a face-off between two popular TV stars: Ruby Rose, the high-profile lead of Batwoman (who also made a high-profile exit from the series after a single season) and Sam Heughan, who's played the dreamy Jamie Fraser on Outlander for the past five seasons. Not only does the movie deliver on that promise, it also constructs an action-packed story around the pair that makes for an entertaining, if not groundbreaking, diversion.

The film centers on Heughan's Tom Buckingham, an operator with the SAS, a special forces unit of the British Army. Tom is sent to apprehend the Lewis family, which includes father William (Tom Wilkinson), son Oliver (Owain Yeoman) and daughter Grace (Rose), after a Red Notice for their criminal activities in the Republic of Georgia is issued by Interpol. Of course, there's far more behind the Lewis' actions than meets the eye, so in response to the British government's moves against her family, Grace amasses her team and takes control of a Paris-bound train in the middle of the Channel Tunnel. Grace demands a hefty ransom and safe passage in exchange for the train full of hostages and an implied promise not to reveal what really happened in Georgia. However, things get complicated when Tom happens to be on the same train with his doctor girlfriend Sophie (Hannah John-Kamen), who he's planning to propose to. Tom quickly springs into action to bring Grace and her team down before they can hurt anyone, especially the woman he loves.

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While the plot is reminiscent of Die Hard and the many other movies that have borrowed its basic blueprint, SAS: Red Notice, which is based on a book by former real-life SAS operator Andy McNab, has enough thrills to keep things humming along. Plus, the love story between Tom and Sophie -- and Tom's determination to make it to Paris to propose -- gives the plot extra stakes. Both Heughan and Rose turn in solid performances, with Rose in particular seeming more confident and at ease than she often did playing the hero in Batwoman. Meanwhile, the stunt and action sequences, which include a lot of gunplay and plenty of fights, are well executed and inventive enough to keep viewers invested in their outcome.

Despite the formulaic story, there's one thing that sets SAS: Red Notice apart. In the first moments of the film, before the plot has been put into motion, a voiceover by Wilkinson provides a brief definition of psychopaths: namely, that they only make up one percent of the population, often inherit the disorder and are incapable of love -- except for the even more rare psychopaths who learn to love. After bringing this to the viewer's attention, the film uses it as a jumping off point to make a connection between Grace and Tom and the characteristics they supposedly have in common. Of course, the word "psychopath" has become shorthand for the motivation behind any number of shocking and problematic behaviors -- especially in pop culture -- but psychopathy is still being studied by psychologists and psychiatrists, and what it consists of and how it's diagnosed is not yet settled. As a result, the film's simplistic sketch of the disorder would be far from satisfactory if it were applied to a real person.

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Within the context of the film, though, this setup has mixed results. On the one hand, it creates an interesting way of understanding the two main characters, while also explaining their worldviews. This helps deepen and give additional dimension to Tom and Grace's actions and eventual interplay, positioning them as more alike than their locations on opposite sides of the film's central conflict would otherwise make it appear. On the other, it makes Sophie's willingness to stay with Tom less understandable, especially given her work involves saving people's lives and his often involves ending them. Moreover, this leads to at least one strangely timed interlude where Tom discusses love with a little girl he saves from the train. Still, while no one should believe they have a good understanding of psychopathy after watching SAS: Red Notice, the introduction of the concept at least stirs something different into a tried-and-true formula.

This isn't the most memorable film, but it's a competent actioner that will satisfy anyone who enjoys gritty stories in which one good man goes up against a group of ruthless, well-prepared bad guys. While it's a bit too long and viewers' interest in the film's love story and musings on psychopathy may vary, SAS: Red Notice includes more than enough whiz-bang action to stay exciting.

SAS: Red Notice, starring Sam Heughan, Ruby Rose, Andy Serkis, Hannah John-Kamen, Tom Wilkinson, Owain Yeoman and Tom Hopper, is available On Demand on Tuesday, March 16.

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