“You know what bastards they are.” The anonymous cab driver’s observation of “perfectly normal human beings” in “Harvey” is spot-on.

Fortunately, the Dramat’s production of Mary Chase’s Pulitzer Prize-winning play, which opened last night at the Iseman Theater and runs through Saturday, has this maxim in mind throughout. Material that could be lackluster and lifeless elsewhere is made loopy and laugh-worthy in this show, which encourages us to be attuned to the zany and zippy in our own lives.

Nor should we expect anything less from this entirely freshman-run show. From director Molly Houlahan ’14 and producer Ethan Karetsky ’14 down to the misanthropic cab driver (Connor Lounsbury ’14), who only has a brief cameo, cast and crew are all eager to experiment, eager to bring their own brand of madness to the stage. It is refreshing.

At the center of it all is Harvey, a six-foot-tall rabbit and the best friend of the slick but not-so-sensible Elwood P. Dowd. Harvey may or may not be real. Dowd is delightfully played by Ryan Bowers ’14, who navigates between the sober and silly with aplomb. The rest of the cast’s attempts to maneuver around Harvey’s invisible frame are a tad forced, but this is consistent with Chase’s purpose; we wonder if we too have our own Harveys, if we too make grand motions in the air.

We would not be alone. Dowd’s sister, Veta (Chandler Rosenthal ’14), who is embarrassed by her brother’s fantasy, admits she too sometimes sees Harvey, though never to her guileless daughter, Myrtle Mae (Calista Small ’14). Veta, along with the psychiatrists charged with Dowd’s correction, Drs. Chumley (Jordan Ascher ’14) and Sanderson (Gabe Greenspan ’14), wrestle with the bounds of belief as the play progresses.

Though the play begins slowly, Dowd’s arrival energizes things. Small and Rosenthal unpack a full range of reactions, from terrified anger to sobbing acceptance, impressively amplifying the emotions we experience every day. These feelings are what the lanky Chumley and the sexually awkward Sanderson are supposed to be able to read, but they are incompetent. Luckily, Ascher and Greenspan are not — instead, they wield the jargon and quirks of the psychiatric profession with superb skill, giving us sustained comedy and sure competence.

More serious is the play’s general critique of the legal and psychiatric professions. The bureaucratic Judge Gaffney (Christopher Bakes ’14) forever takes notes but fails to note or do anything interesting in the world. And Nurse Kelly (Laurel Durning-Hammond ’14), an uneasy ancillary to Chumley and Sanderson, is likewise caught amid the workplace mess. Durning-Hammond is particular effective at communicating to us Kelly’s squeamish existence in a world that’s over her head — if we ever don’t understand what’s happening in the play, we can sympathize with Kelly, who doesn’t get what’s happening with her life.

The psychiatry clinic, represented by a simple, walled set, is the focal point of Chase’s drama. Our own lives may seem distant from this sterile and soul-crushing environment where the gruff orderly Wilson (Sharif Youssef ’14) oversees mental improvement. But we should remind ourselves that we live in a psychiatric ward of sorts, one in which the crazy are, in fact, sane, and the real threat is from the normal.

Sanderson makes at least one correct diagnosis: “Being human, [we] are liable to make mistakes.” This production, a thoroughly human one, is not exempt.

The actors are tempted to undue extremity at times — one scene in particular, where Wilson and Elwood are on the verge of combat, is a trite farce. Likewise, the domestic scenes set in Dowd’s house slow the play down. Though these lull are not unwelcome, they are tedious in comparison to the shenanigans in the rest of the show.

Still, these issues do nothing to detract from the play’s design, which is to surprise us with — and give us solace in — our own lunacy. Even if we have our own Harveys, even if we feel trapped in our own psychiatric ward, even if we have sold out to the bureaucracy, this deft production leaves us with some peace of mind.