Sean Hayes stars in a lazy off-Broadway thriller

During the first season of the NBC sit-com “Will & Grace,” Sean Hayes’ character Jack created a one-man cabaret show for himself succinctly called “Just Jack.”

Nearly 30 years later, the actor-turned-podcaster finally has a solo effort in real life — “The Unknown” by David Cale. However, the play, which opened Thursday night at Studio Seaview, could be titled “Just OK.”

It’s a suspense drama, in intent more so than effect, that moves at a rapid clip while being highly uncertain of where it’s going, much like a confused newcomer to the story’s setting — Manhattan’s twisty West Village.

Actually, that nabe’s twists are more fun than this play’s. At least you might wind up somewhere cool.

In a departure for the typically taut, heart-racing genre, “The Unknown,” directed by Leigh Silverman, starts out tense, loses its bearings and sputters to an open-ended finale.

Hayes plays Elliott, a lonely, single playwright with writer’s block. That’s a tee-ball-easy set-up if there ever was one. Needing inspiration, Elliott heads to his friend’s remote country house, where one night he faintly hears an eerie song in the distance. 

It’s called “I Wish You Wanted Me” from a musical he’d written years earlier. What’s spooky is that he can’t locate the anonymous crooner in the woods. 

Meanwhile, in the theater seats, our uneasy sensation comes from the fact that the melody closely resembles “Sing once again with me our strange duet!” from Andrew Lloyd Webber’s “The Phantom of the Opera.” Good thing there are no giant chandeliers to come crashing down at Studio Seaview.

When Elliott arrives back to his apartment on Bank Street, the first of a few half-gasps arrives: A piece of paper with the words “I wish you wanted me” scrawled on it is taped to his front door. Is he being stalked? And — lightbulb! — is this frightening scenario the perfect idea for the script he needs to write?

Already “The Unknown” begins to unravel. A character willingly putting himself in extreme peril while attempting to solve a mystery for the sake of a good yarn is frankly a bit “Nancy Drew” for me. And, though dubbed a thriller, the play is too capering and sparse on details to make any viewer sweat, let alone jump. Scary, it is not.

Hayes, unsurprisingly, fares better with jokes and funny glances than paralyzing dread.

The actor won his first Tony Award in 2023 for playing witty pianist Oscar Levant in “Good Night, Oscar,” which took full advantage of his comic (and musical) strengths. 

Cale’s show forces the actor to pare down his ticks and tricks.

True, he theatrically pops into several roles this time, including the narrator, his friend Larry, Larry’s soft-spoken wife Chloe, a forward Texan named Keith he meets in Julius’ bar and others. But Hayes is admirably calmer and less mannered than he was on Broadway.

That said, his chosen voices for the non-Elliott parts can be rather brow-raising.

For instance, Larry, the pal he once had feelings for, gets a throaty Walter Cronkite brogue. Who has the hots for Walter Cronkite? And his British accent for another person gives Dick Van Dyke newfound reason to hold his head high.

Still, Hayes is good enough, and ticket buyers like him. The play’s the problem. The side characters are lifelessly written, and the plot doesn’t add to or reinvent the airport paperback cliches it’s built from. Oh, look, an intruder sitting on a chair in the dark. Where have I seen that before? Everywhere!    

Cale, the usually excellent monologist, has become a James Patterson of late, penning thriller after thriller as the quality descends. In 2017, his “Harry Clarke,” about an American man who pretends to be British, was much more original and satisfying. 

And his brave 2019 semi-autobiographical solo show, “We’re Only Alive For a Short Amount of Time,” hinged on one of the most shocking revelations I’ve ever experienced on any stage.

Next to those, “The Unknown” is an altogether sedate sit, sporadically livened up by the presence of its marquee star.

Perhaps one could argue that Cale’s latest, in which mimicry and stolen identities play a major part, is devoid of personality by design. The ending would suggest that the play itself might be borrowing from others as well. I even wondered if that repeated “I wish you wanted me” tune was made to sound like “Phantom” on purpose.

Is imitation the highest form of flattery? Maybe. But “The Unknown” is simply flat.