Classic Stage Company’s revival of “Hamlet” has its audience on their feet from the very start. This has little to do with the revival itself, which seesaws between exhilarating highs and exasperating longueurs, and everything to do with the odd decision to begin the play by turning the entire audience into unwitting groundlings. Ushers herd the spectators onto Mark Wendland’s immaculate white set as the first scene unfolds around them. (And among them: I heard one playgoer mutter before being allowed to find his seat, “The Ghost just stepped on my foot!”)

That pristine white won’t last: By the end of Brian Kulick’s robust but murky production, anchored by the dependably insightful Michael Cumpsty in the title role, the walls will be slashed, torn, and covered with everything from spray paint to mud to blood. As Elsinore gets messier, it also gets faster, with Mr. Kulick ramping up the tempo as the bloody doings commence.

Mr. Cumpsty spits out his entire “the readiness is all” monologue in about the time it took him to get through the first four lines of “O that this too too solid flesh” early on. Robert Dorfman’s overcaffeinated, wild-eyed Claudius, meanwhile, manages to get through pages of dialogue in the same amount of time. As with the Broadway revival of “Sweeney Todd,” which also features a slimmed-down cast and a black-andwhite (plus some red) color scheme, the emphasis on visceral experience over clear narrative might be savored by devotees but could prove baffling at times to newcomers.

In the terrific recent miniseries “Slings & Arrows,” set at a provincial Canadian theater festival mounting “Hamlet,” the director counsels his terrified star, “Nail those six soliloquies, everyone goes home happy.” Few would object to Mr. Cumpsty letting his honeyed baritone linger over these set pieces a bit. Instead, he and Mr. Kulick underplay them. One, “What a piece of work is a man,” is even performed from a supine position, as Hamlet looks at clouds with Rosencrantz and Guildenstern.

As a result, these speeches are reduced from elaborate, state-of-the-Dane addresses to quick glimpses of Hamlet’s precarious condition. Mr. Kulick seems more interested in exploring just how crazy Hamlet becomes, whether he is feigning madness to expedite his detective work or whether he really can’t “tell a hawk from a handsaw.”

Messrs. Kulick and Cumpsty appear to lean toward the latter interpretation, as the initial sight of the ghost of Hamlet’s father (Jon De-Vries) shifts Hamlet’s dour mood to unhinged fanaticism. You get the impression that Hamlet’s vacillations aren’t completely within his own power, even if he believes they are.

This mercurial nature can’t be blamed on youth: Indeed, most of the off-stage discussion about this production has centered on its Hamlet’s relatively advanced age. To my eyes, it’s irrelevant. Hamlet’s defining characteristics – the indecision, the mood swings, the impulsiveness – are hardly exclusive to adolescents. It takes experience to convey Hamlet’s torrent of emotions as efficiently and skillfully as the grim-visaged Mr. Cumpsty does. Plus, if Elizabethan audiences could handle a 15-year-old boy playing Gertrude, as he has pointed out in interviews, we can deal with a 45-year-old Hamlet.

Mr. Cumpsty’s cloud-gazing bit is hardly the only bit performed from the ground. Mr. Kulick has pared his cast down to nine – the last Broadway revival had almost triple that number – and keeps nearly all of them writhing, leaping, and dancing all over the increasingly grimy set. (For all of Mr. Kulick’s innovative spins on the play, he also hews to the current tendency to have Hamlet throw both his mother and girlfriend around like rag dolls.)

Given his overall tendency to push the story along, Mr. Kulick’s overindulgence of the scenes involving the Player King (Mr. DeVries again) and Queen (Jason Ma) is puzzling. These sequences, along with a frequently unintelligible Mr. Dorfman, mark the only real missteps among the performers. Caroline Lagerfelt’s Gertrude frequently seems anesthetized but musters up the required energy for the Act III confrontations; Kellie Overbey fares better with her touching, steely Ophelia; Herb Foster is a delight as a doddering Polonius; and Graham Winton and Karl Kenzler represent the younger set with particular verbal acuity.

“Use every man after his desert,” Hamlet sighs, “and who shall ‘scape whipping?” Not many people do in Mr. Kulick’s rambunctious production: The show ends with five of its nine actors as corpses (plus a drowned Ophelia off stage). The rest is silence, indeed. But this climax is beautifully realized; Mr. Kulick makes it absolutely clear at all times who knows what about which murderous schemes.

That sensitivity to where each character is, emotionally as well as physically, is what’s missing too often from Mr. Kulick’s excitable production. With a little less writhing and wall smashing, and a little more silence and clear storytelling, Mr. Cumpsty’s resourceful, keen-eyed interpretation might have gotten the room it deserves.

Until December 11 (136 E. 13th Street, 212-279-4200).