A play centered around a missing 14-year-old boy might sound like grim or depressing fare. But, in the case of The Absolute Brightness of Leonard Pelkey, now onstage at Florida Studio Theatre’s Keating Theatre, it’s not. Sad, yes, but with welcome flashes of humor and hope, too, in the hands of playwright James Lecesne, director Kate Alexander and one-man cast Jeffrey Plunkett.

Plunkett, who’s appeared in a number of FST shows before, plays all the roles in this short but effective play, starting with the police detective who’s investigating Leonard’s disappearance. As Chuck, he’s tough on the surface, telling us about the dark side of his job even while admitting that, in a small town on the Jersey shore, there isn’t all that much crime for him to solve.

But when hair salon owner Ellen and her daughter Phoebe come to his office to report that Leonard’s been gone for nearly 24 hours, Chuck actually has a case, one that brings him into contact with others in town who knew and were impacted by Leonard. Although all we see of Leonard is a purposefully blurry photograph (projected on the changing sky pattern background of Stephen Dunham’s set), we get to understand a lot of his flamboyant personality as Chuck interviews townspeople, from a British theatrical school owner to a birdwatching Mob widow to an old clock store owner who saw in Leonard something of the homosexual son he lost.

For yes, Leonard is decidedly different from the other boys—and adults—in his town, from the rainbow platform sneakers he’s devised for himself to his desire to display fairy wings as Ariel in a production of The Tempest to his wearing of make-up and outlandish clothes. For some, this difference is a concern. Ellen, his surrogate mother/aunt figure, worries that he’ll be bullied (and he is); for Phoebe (“16 going on 45”), having to defend him at school and with their peers grows exhausting. For the taunting teenage boys Leonard has to face every day, he’s a threat to their understanding of maleness.

And for others, Leonard’s insistence on being himself, who he really, truly is, is something of an inspiration. That’s what it ultimately is for Chuck, even as his search for answers leads down some unhappy avenues.

Thanks to Lecesne’s sensitive writing, Plunkett’s gift for shifting voice and manner to represent the different characters here (with just a few props and no change of costume, he uses body posture and gestures to delineate, say, a hard-edged, cigarette-smoking woman or the fey Brit), and the actor’s empathetic partnership with director Alexander, we get a nuanced portrait of Leonard and those in his orbit. It’s a touching show, and one that deserves the applause Plunkett received the night I saw it.

The Absolute Brightness of Leonard Pelkey continues through Aug. 6; for tickets call (941) 366-9000 or visit floridastudiotheatre.org.