Actor Glen Powell solidifies his leading-man status by radiating reams of charisma and talent in the new movie “Hit Man.” Making good on his star-marking turns in “Top Gun: Maverick” and last year’s “Anyone But You,” the actor alternately plays brainy, hunky, awkward, confident, reckless, non-threatening, sharp, and average in the film. In the process, he subverts the stereotype of the “hit man” character and even comments on acting and fame itself. That he also co-wrote the screenplay with his director, Richard Linklater, only proves that Mr. Powell is the real deal.

Having its premiere Friday on Netflix, “Hit Man” ostensibly deals with contract killing, yet the movie’s primary interests lie in philosophy, society, and the nature of identity. Think of its thriller setup as a MacGuffin, with the genre giving the film some momentum and danger, though it’s really more of a romance, personality game, and meta-commentary on stardom. Indeed, early on in the film, Mr. Linklater dismisses the entire concept of murder-for-hire as a cinema construct through a montage of movie clips, including ones from a Charles Bronson actioner, the Japanese noir “A Colt Is My Passport,” and the dark comedy “In Bruges.”

Mr. Powell portrays Gary, a University of New Orleans professor and dabbler in tech support for the city police. One day, he’s asked to step into the role of a fake hit man in a sting operation, despite having no real experience or education in the field of undercover policing. As with most movies, viewers must suspend any nagging disbelief at such an unlikelihood, and yet this improbability opens the film up to its main thesis: Whether a person can become someone else, and whether people can change.

Based on Gary’s success with his first undercover job, the answer is a resounding yes. Gary steps into his “hit man” alter-ego with ease, embellishing his persona with plausible details. He even employs weird physical characteristics and makes amusing sartorial choices for meetings with murderers-by-proxy, some of whom we see a bit later in a couple of courtroom scenes that come off like a sociology class crossed with a Frank Capra movie. Moments of Gary’s police force cohorts marveling at his transformation, interspersed with scenes of him lecturing students, add to the film’s comic and lightly philosophical tone.

Complications arise when Gary, using the hit man moniker Ron, meets Madison, an unhappy housewife who wants her controlling husband killed. Their first encounter has the feel of a noir-like assignation, a twisted job interview, and a meet-cute all in one. As they joke about pets, discuss her marriage, and even ponder life choices, the Gary inside of “Ron” realizes that Madison is just a deeply misguided woman, and so he summarily refuses her incriminating money and advises her to leave her husband. Her beauty plays no small part in his decision, and though his co-workers later rebuke him for allowing a conspirator off the hook, he’s allowed to keep plying his newfound trade.

Naturally, after some time has passed and Madison has followed his advice by starting the divorce process, Ron hears from her again, though this time it’s not to plan a murder. The two begin to date, and while there’s an acknowledgement of the murky ethical waters Gary’s wading in by seeing a former suspect, the topic is quickly set aside, especially since there are sex scenes to depict and suggestive, mock-dangerous banter to exchange. (The film is another example of Hollywood’s re-embrace of physical intimacy and the playfully erotic.) It helps that Mr. Powell and Adria Arjona as Madison have undeniable chemistry.

Messrs. Linklater and Powell based their screenplay on a Texas Monthly article published more than 20 years ago about a real-life undercover contract killer, expanding on a few sentences that mention his involvement with a woman looking to off her ex-husband. In the film, the couple vow to keep their relationship impersonal, with Gary particularly eager not to have her know he’s not actually a hit man. This brings us into prime romantic comedy territory, with deception and role-playing being part of the fun. The course of true love never did run on lies, though, and when a cop co-worker finds out about the affair and Madison’s husband turns up dead, the moral and criminal elements the characters have been toying with catch up with them.

“Hit Man” itself flirts with serious subjects like complicity and justice — both sanctioned and poetic — and its comic tone turns decidedly dark when it alludes to “la petite morte” during its climatic scene. Yet its focus remains on the notion of personality and the aspiration to become a bolder person.

At times, this stew of philosophy and psychology overwhelms the narrative, rendering it overly talky, unsubtle, and visually bland. Still, Mr. Linklater has pulled off something rare these days: an entertainment rich with ideas that’s also sexy and funny. And Mr. Powell, combining Matthew McConaughey’s easy charm with Tom Cruise’s intensity, joins Hollywood’s rarified firmament of true stars.