We’ve seen this before: The suspects are gathered, the murderer is about to be unmasked. An announcement is made, freighted by the “sturm und drang” of a crashing organ’s minor chord in a Wagner opera. “Someone,” says an investigator, “sticks out like a sore thumb.” Pregnant pause. And then, with the slavishly ominous portent of Cassandra at Delphi, “Should I say thumb-one?”
The crowd goes wild.

‘Murder for Two’
★★★
When: Through Aug. 26
Where: Marriott Lincolnshire Theatre, 10 Marriott Dr., Lincolnshire
Tickets: $50-$60
Info: MarriottTheatre.com
Run time: 90 minutes, with no intermission

If you like puns, Agatha Christie, playing “Clue,” the Marx Brothers, “The Carol Burnett Show,” “The Little Rascals” and/or unnecessary farces, “Murder for Two” is your cup of (poisoned) tea. And if you don’t, maybe consider lightening up! Joe Kinosian and Kellen Blair’s two-actor, 13-character whodunnit is pure, escapist ridiculousness. And who among us does not need that every now and again?

Note: This is a whodunnit wherein it doesn’t matter two twigs whodunnit. The point of the 90-minute exercise is comedy: Puerile, derivative, more low-brow than the missing link and delivered with virtuosic physical, verbal and musical timing. Directed by Scott Weinstein, “Murder for Two” is, in short, a guilty pleasure.

The frenetic musical comedy stars Noel Carey and Jason Grimm. Carey plays Marcus Moscowicz, an ambitious small-town cop called to the scene of a surprise-party-turned-homicide. Grimm plays all 12 suspects. Both of them play the piano throughout, accompanying themselves, each other and providing ambient music.

Technically, the show is a beast. That piano playing is constant, rapid-fire and live. Moreover, there’s no orchestra to drown out any misfires. Music director Matt Deitchman makes the fast-paced score seamless as it hurtles the plot forward. Grimm and Carey make it look effortless.

Weinstein makes sure his compact cast brings out the musical’s blatantly self-deprecating self-awareness. Never mind the unsolved murder of one Arthur Whitney. As “Murder for Two” somberly intones, what we are really witnessing is “the slow, painful death of the American theater.” The true tragedy is that we’ve come to this: A show that rhymes “Ikea” with “diarrhea.”

“Murder for Two” celebrates its derivative nature. The musical numbers include vaudeville hoofing (Grimm, playing a “12-man boy’s choir”), boffo 11 O’Clock power-anthems (enhanced by no less than eight disco balls descending from on high) and novelty numbers (a rando fireman named Vivaldi gets a pointless and hilarious number).

Depending on your family, the show not entirely family-friendly. One slightly randy vignette features Murray and Barb (Grimm), a cantankerous old married couple. Think of Murray as Inspector Javert on crack and Barb as Eunice, the demanding mother in “The Carol Burnett’ Show’s” seminal “Mama’s Family” sketches.

Grimm has (arguably) the showier role. As prima ballerina Barrette, he smolders like the ruins of the last Romanovs. As the endlessly needy psychiatrist Dr. Griff, he is the banana peel that instigates a thousand Freudian slips. And as Arthur’s performance-driven widow Dahlia, he could star in a spinoff to “Waiting for Guffman.” Carey’s Officer Moscowicz has the rubber-band dexterity of the late, great Ray Bolger and an expressive face that puts the mug in mugshot.

Everything plays out on Scott Davis’ eccentric set design, which is part Victorian grandeur (grand piano, parquet floor, more chandeliers than the Drury Lane theater) and part sheer madness (giraffes, bongos, trunk).

You will not leave “Murder for Two” any smarter than you went in. Who cares? This is one killer musical comedy.

Jason Grimm (left, as one of 12 “Suspects”) and Noel Carey (left, as Marcus the detective) in the Marriott Theatre production of “Murder for Two. ” | Liz Lauren