What a tepid treatment of an intriguing piece of murderous plotting “Measure of Revenge” turns out to be.

It’s a star vehicle for Oscar winner Melissa Leo in which she plays a grande dame of the theater, a woman famous for witches and murderesses and divas, whose past roles come to advise her on how to avenge the death of her musician son. The twist, once “legendary” Lillian figures out who caused her lad’s death, she uses her nightly “on the stage” alibi as a way of covering up the killings.

One by one, down they go, with our heroine stop-watching herself between her character’s appearances in a show of her own devising.

Yes, it’s plotted like a “Columbo” episode, or two or three. In this case, it’s a clever idea utterly botched in the production.

Lillian has just gotten her star singer-son Curtis (Jake Weary) out of rehab, he’s just shown her the ring he plans to give his pregnant girlfriend (Jasmine Carmichael) when he turns up dead on a night Lillian wasn’t following orders to “never let him out of your sight” from the rehab team.

Both her son and his fiance-to-be overdose, “accidentally” the detective (Michael Potts) on the case declares. But he’s a theater fan who hears the stage legend out when she claims her kid was clean, that no way would he and his pregnant wife-to-be have been using some dangerous new drug flooding the city. And he’s also understanding, paying a courtesy “warning” call when she starts sniffing around, finds out who used to be her boy’s dealer and confronts Taz (Bella Thorne) in her car.

Lillian has met her son’s oily record producer (Kevin Corrigan, on-the-nose casting), who’s tactlessly said “You know Curtis is gonna be a bigger star than ever before,” now that he’s OD’d.

She’s used Taz — a photographer who moonlights as a drug dealer, or vice versa — to ID other people in her son’s orbit who might have caused him harm, accidentally or on purpose. She’s staked out those folks, found ways to size them up.

And she’s seeing all the murderous figures from her theatrical past, hearing voices of Shakespearean characters and Poe killers. They’re egging her on, and once they’ve got her convinced, there’s no turning back.

The sound design in the film tries to simulate Lillian’s frazzled state of mind with an aural blur of mostly-unidentified characters badgering her, giving her advice with lines from plays or short stories. Visually, she sees badly-rendered “ghosts” of characters past (Leo in different costumes) in bathroom or dressing room mirrors, even physically in the room with her.

Leo does her best, but the film has little pace and the production seems malnourished in ways that call attention to why this or that big murder moment lands flatly. The camera isn’t in a position for maximum dramatic impact, the music is off and the editing so static as to render even the murderess’s performance flat.

There’s no suspense to the cop’s curiosity about these “connected” murders.

The directing credit here goes to someone named “Peyra,” apparently the “directing” name of producer Peter Wong. “Alan Smithee” is a little too white bread for him, I guess. And there is no writing credit. If you see “Measure of Revenge,” you’ll understand why one wanted to use an assumed name and the other wasn’t clever enough to come up with one.

Rating: unrated, violence, drug content

Cast: Melissa Leo, Bella Thorne, Jake Weary, Michael Potts, Adrian Martinez, Jasmine Carmichael and Kevin Corrigan.

Credits: Directed by Peyfa, scripted by ? A Vertical release.

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