There are too few contemporary plays that are instant classics, but Tom Stoppard's 20-year-old masterwork Arcadia is one of them. It's dense with language yet buoyant in style, speaking to the present as much as the past, and as light on its feet as its performers must be, waltzing between two centuries, and dancing the fine line between comedy and pathos. A.C.T.'s new production of the play is an honorable revival, neither too ambitious nor too astonishing, but a fine rendition of an extraordinary text.

We'll begin by saying that we saw the original American production of Arcadia in 1995 at Lincoln Center in New York, directed by Trevor Nunn with a stellar cast including Victor Garber, Robert Sean Leonard, Blair Brown, Billy Crudup, and Paul Giamatti. It remains a standard-bearer in our mind of what great theater should be — affecting, enlightening, moving, funny, and mind-blowing in its scope. Not all playwrights are up to all those tasks at once, but Stoppard most definitely was when he wrote this piece in the early 90s, operating at the top of his game before writing other modern classics The Invention of Love and the Tony-winning The Coast of Utopia.

The play tells the parallel stories of two sets of characters, one in 1809 and the other in the present day, both sharing the same ancestral English estate called Sidley Park. (Despite having been written over 20 years ago, Stoppard's text feels as current and relevant as it could be, despite lacking any references to cell phones or the internet.) In 1809 you have a handsome tutor, Septimus Hodge (played by the confident and funny Jack Cutmore-Scott), and his 13-year-old charge, Thomasina Coverly (the articulate and bubbly Rebekah Brockman, who does an admirable job of maturing in Act 2 as a 17-year-old). And you have a supporting cast of characters both seen and unseen, including Thomasina's mother Lady Croom (Julia Coffey), Captain Brice (the woefully underused and talented Nick Gabriel), a third-rate poet and aristocratic hanger-on named Ezra Chater (Nicholas Pelczar), and Lord Byron himself. Also, you have a minor drama unfolding over the redesign of the gardens at Sidley Park at the hands of designer Richard Noakes (A.C.T. company member Anthony Fusco).

The design of the garden is, in 1809, following fashion and transforming from something formal, symmetrical, hedge-lined, and Italianate into something more "natural," Gothic, and brooding. This is used as a metaphor for this moment in English history both by Stoppard and by modern-day academic character Hannah Jarvis (the excellently cast and superlative Gretchen Egolf), who's researching a book that centers the garden and on a person known only as the Hermit of Sidley Park, who is her own discovery. She's joined in the present day by fellow academic, Bernard Nightingale (played with great, irritating boorishness by Andy Murray) — who's come here on a mission to prove that Lord Byron passed through this house at a significant moment in his life — and the equally intelligent but scientifically minded Valentine Coverly, one of the current residents of the house, who's at work on his own mathematics study. While engaging in several romances and interpersonal dramas, these character intersect and debate their intellectual pursuits, speaking across two centuries about the same mysteries, and seeking the same sense of revelation.

The play is such a delightful puzzle, remaining witty and hilarious throughout its two and a half hours, that it's impossible to summarize. Stoppard has filled the text, like Shakespeare himself, with dozens of quotable and brilliant lines, many concerning the human search for knowledge and meaning. "It's wanting to know that makes us matter," says Hannah, during the climactic second half of the play. "It's the best possible time to be alive," says Valentine. "When almost everything you thought you knew is wrong." And, in the final scene, Septimus says, "When we have found all the mysteries and lost all the meaning, we will be alone on an empty shore."

Because of the density of the dialogue in Arcadia, and the complex choreography of the second act in which the characters from both centuries begin sharing the stage, it is not the simplest play to pull off perfectly. Even the aforementioned Lincoln Center production was deemed imperfect by the New York Times, in part because of the casting, and the same thing affects A.C.T.'s effort. While much of the comedy comes off well, not all the performers are up to the verbal gymnastics of the text, allowing some scenes to seem clunkier than they should. As Lady Croom, Ms. Coffey is a bit too stereotypically affected in her aristocratic speech while so many of her peers are spitfiring their lines at a different rhythm. And while most of the accents come naturally enough to these actors, Mr. Fusco's attempt at an unidentifiable, regional British English sounds awkward and the most forced.

In the moments in Act 2 when the momentum should be at its peak and the performers should be effortlessly circling, recircling, and dancing between each others' lines and feet in a well-timed waltz, there are too many missed beats and changes in tempo for it to feel effortless. Carey Perloff's direction, while mostly hands-off for much the play — following Stoppard's intricate stage directions and using a simple but elegant set by Douglas W. Schmidt — is most needed here and feels the most lacking during these subtle stumbles. But it is the kind of thing that will evolve during the run, and maybe all these actors need is another week to get the rhythms down.

Lighting effects, by designer Robert Wierzel, are inventive and lovely throughout. We'll also mention that the music (written by Michael Roth), while somewhat innocuous and at soft volume, plays such a crucial role throughout the play that we longed for it to be more melodic and prominent in certain scenes.

Regardless of some minor flaws, we're grateful to have gotten to see the play staged again, and to hear how well Stoppard's words have held up despite those twenty years. It's a play that demands to be listened to and contemplated, and astounds on every level.

Arcadia plays through June 9 at A.C.T. Get tickets here.