When last she passed through a doorway that changed world drama, Nora Helmer was an agitated young wife, leaving behind a husband and children and forging, via Henrik Ibsen’s “A Doll’s House,” a revolutionary path for women suffocating in unhappy marriages.

Now, 15 years later, she’s back at that door in “A Doll’s House, Part 2,” and the revolution is far from over. Lucas Hnath’s inspired sequel — which starred Laurie Metcalf in a Tony-winning turn on Broadway two years ago — is being freshly mounted by Round House Theatre in an intelligently crafted production that doesn’t leave you quite as exhilarated as it could. Some essential crackle has yet to be ignited.

Mind you, the company and the director, Nicole A. Watson, have assembled top-drawer players for the quartet of characters in this evening of confrontational domestic aftershocks at the Lansburgh Theatre. Holly Twyford assumes the marquee role of Nora, and it’s a becoming psychic merger. Her Nora, handsomely swathed in Victorian finery by costume designer Helen Huang, is a woman of intriguing contradiction: serenely contented with the liberated life she has created for herself and yet unable fully to accept responsibility for the pain her abrupt departure (at the famous end of “A Doll’s House”) engendered.

The self-assurance Twyford effectively projects lays a tantalizing groundwork for the blowback she gets from husband Torvald (a somber Craig Wallace), housekeeper Anne Marie (a fine, anxiety-ridden Nancy Robinette) and daughter Emmy (a rewardingly assertive Kathryn Tkel). The bulk of the tension in “A Doll’s House, Part 2” is generated by the peculiar request Nora is forced to make of Torvald; what Hnath mines here is the cruel ways that marriage — and the history of legal inequity in contracts between partners of different genders — can keep a woman in chains to a man, long after a union has dissolved.

This issue of longevity in a marriage fascinates Hnath, and his taut, always well-reasoned dialogue pulls you into his preoccupation. “I think it’s good to be stuck in a marriage,” says Tkel’s Emmy, who shocks Nora with her conventional frame of mind. For anyone who loves Ibsen’s work, it’s a clever turning of the tables on a great playwright who claimed freedom of the soul and spirit as a theme in play after play.

The line also brings to mind Hnath’s subsequent play about a troubled marriage: “Hillary and Clinton,” which is now on Broadway, with, yes, Metcalf as the former first lady, senator and candidate for president. The linkage is the idea of the “lock” in wedlock. Emmy seems a creation halfway along a spectrum between Nora, who thinks marriage should be abolished, and Hnath’s Hillary, for whom it is inextricably tied to destiny.

On the occasion of “A Doll’s House, Part 2,” Hnath may count too heavily on the audience’s familiarity with the source material, because knowing the original does indeed enrich the experience of the sequel. In other cases, theatergoers with an aversion to Ibsen — this pioneer of lyrical, dramatic naturalism strikes some as a bit dry and polemical — may make the decision not to attend on the basis of the title alone.

I’m here to tell you, though, that “A Doll’s House, Part 2” — which unspools in 90 short minutes — is a worthwhile event, even if Watson’s production could dial up the tension a smidge. The set by Paige Hathaway intriguingly suggests a household that has atrophied in Nora’s absence: Banker Torvald’s parlor looks emptied of personality, with paintings and picture frames and lighting fixtures haphazardly propped against walls, as if ready for the movers.

In the encounters that follow, nicely delineated by Harold F. Burgess II’s superior lighting, you do need to see more of Nora’s composure come apart, especially after she meets up with the surprising Emmy. That sense of each family member chipping away at the armor acquired in 15 years of independence is crucial to the dramatic issue that must hang in the balance: Will Nora leave again? Wallace and Twyford have a responsibility, too, to allow us to intuit some measure of feeling rekindled, to activate the tenseness, and at present this aspect feels underdeveloped. These are subtleties of character that I suspect, in Hnath’s humorously understated fashion, take time to master.

Still, this is a bracingly lucid exercise, one that will have you setting up a spreadsheet in your imagination, of the pluses and minuses of what it means to be legally, if not to say, spiritually, bound to another person. And the outcome is illuminating enough to wonder what would happen in Part 3.

A Doll’s House, Part 2, by Lucas Hnath. Directed by Nichole A. Watson. Set, Paige Hathaway; costumes, Helen Huang; lighting, Harold F. Burgess II; sound, Roc Lee. About 90 minutes. $54-$71. Through June 30 at Lansburgh Theatre, 450 Seventh St. NW. 240-644-1100. roundhousetheatre.org.