By Jocelyn Noveck

Even if, like me, you've never been to a Harry Styles concert, it's hardly difficult to comprehend his huge appeal. He's … Harry Styles.

Also huge, to his many fans: the very news of Styles starring in a movie. (Or, did you happen to miss the circus surrounding his appearance in "Don't Worry Darling"?)

But "huge" is not the word to describe Styles' performance in "My Policeman," a deliberately paced, melancholy period piece about love, loss, pain, prejudice and the danger of living inauthentically. The biggest challenge for Styles, and for the studio that lists him as one of a six-actor ensemble — albeit at the top of the list, they're not stupid! — is to mute the confident pop-star magnetism, in service of the story. This he does. At times, though, it seems he's pressing too hard on that mute button, erasing personality from his portrayal.

To be fair, much of this may stem from choices by director Michael Grandage and screenwriter Ron Nyswaner, who fashion Styles' character, Tom, a working-class policeman who hides his gay relationship while in a heterosexual marriage, as a blank canvas onto whom others project their desires. There's been criticism that Styles gives an underdeveloped performance, but that ignores the fact that his very character IS underdeveloped, and that's perhaps the point. How can we know him if he does not know himself?

Still, it's a striking contrast with a sharply drawn portrayal like that of David Dawson as Patrick, Tom's lover. Or that of Rupert Everett, who plays older Patrick without benefit of language, in the aftermath of a serious stroke.

"My Policeman" is based on the novel by Bethan Roberts, who has described being inspired by the life of famed British novelist E.M. Forster and his love triangle with a London police officer and the officer's wife, who became a good friend. From this, Roberts fashioned a 1950s-based story about a similar trio but with a devastating, terrible twist — yet grounded in the same shocking historical reality: It was a crime for men to have sex with each other in England until 1967 — and even later in Scotland and Northern Ireland.

We begin in the 1990s (the movie will toggle back and forth between two eras 40 years apart, a choice that weakens the momentum) with Marion (Gina McKee), inviting older Patrick to recover at her home on the picturesque Brighton coast rather than in a depressing care home. Her husband, Tom (Linus Roache) is furious that she's welcomed this man into their home, though we don't know why for now. Tom orders her to send Patrick away, but she refuses.

Now we flash back to the 1950s, with the younger Tom (Styles), soft-spoken but devilishly handsome, wooing the winsome Marion (Emma Corrin, a memorable Princess Diana in "The Crown" and well-cast here) by teaching her how to swim. It's a chaste courtship. One day Tom invites Marion, a schoolteacher who loves art, to a private gallery tour, courtesy of a curator he's met while out on his beat. This young curator is Patrick, and he's all the things Tom isn't: intellectual, worldly, highly cultured.

But Marion remains attracted to Tom. And one night, Tom pops the question — seemingly out of the blue, because they have barely even touched. Patrick toasts them at their wedding. He even shows up during the honeymoon to cook a fancy dinner. All goes well until Tom bafflingly blows up at Patrick at the dining table; this is not the most convincing moment for either Styles or the screenplay.

In any case, all this is Marion's memory of their courtship. There is another version. It's one that older Marion reads about in Patrick's diaries, in a box of his belongings. We then return to the same scenes from Patrick's perspective, to see that all along, Tom was having a passionate affair with Patrick — a passion Marion and Tom never achieved.

While the sex scenes between Tom and Patrick are the ones that generate all the heat, his marriage to Marion is not loveless. They do have a genuine union, and Tom tries, for better or for worse, to have both Marion and Patrick — only partly because his gay relationship must remain secret or they could both end up in prison.

Tragedy soon strikes, and it is painful not only to watch what happens to the relationship between the three, but to be reminded of the terrible way gay men were treated in Britain only some 50 years ago.

It is, finally, Everett's face, lined with sorrow, that haunts the final tableau, a compelling few seconds that brings some closure to a sad couple of hours and gives us, perhaps, a slight ray of hope in the human capacity to heal.

As for Styles and his movie-star prospects? Give him some time. After just two major roles, the jury's still out.

"My Policeman," a Prime Video release, has been rated R by the Motion Picture Association of America "for sexual content." Running time: 113 minutes. Two and a half stars out of four.

Jocelyn Noveck is an AP national writer

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