I always admire an experiment on the stage, whether it falls apart before the end, or succeeds wildly, or falters a lot from the start, or succeeds just enough to keep my attention and applaud its daring. The Last Five Years, a fifteen-year-old piece of musical theater composed and written by Jason Robert Brown — whose main Broadway credits include the short-lived Parade and Honeymoon in Vegas as well as the Tony-winning score for Bridges of Madison County — falls into that latter category of experiments. A new production just opened at ACT Wednesday, directed by Michael Beresse that shows off Brown's work in a fine light, and much like a recent Broadway mini-hit, Tom Kitt and Brian Yorkey's If/Then, it's a daring if sometimes disjointed way to tell a story about love in an unconventional way.

Love stories have been the bread and butter of musical theater since the first ingenue stood in front of the first footlight, and if you're going to tell a love story on stage in the 21st century you're better off blowing the genre up than you are sticking to the standard boy-meets-girl, boy-marries-girl, boy-divorces-girl script. Brown's answer was to tell the story from both the woman, Cathy's perspective, and the man, Jamie's perspective, with one starting from the end and the other from the beginning. We begin with Cathy singing a song of wrenching heartbreak and frustration, post-breakup, called "Still Hurting," and with Jamie singing excitedly about their thrilling first kiss and discovering his "Shiksa Goddess."

Jamie (Zak Resnick), a 23-year-old prodigy of a novelist immediately sells his first novel, heads out on a book tour, and ends up having an affair as Cathy (Margo Seibert), a not-so-successful actress heads out on failed auditions and ends up doing summer stock in Ohio. One gets the sense there are autobiographical elements to this piece, with Brown himself landing his first gig scoring a Broadway show in his twenties, and this leads to some not so subtle elements of gender bias in the story. The character of Jamie is confident, clever, and confused when his girlfriend gets tired of going to book parties with him — and when he cheats the situation is only told from his perspective, and we're meant to sympathize with his needs. Meanwhile Cathy comes across as flighty, insecure, and ultimately jealous and clingy when she begins to sense Jamie drifting away.

Brown's songs throughout are musically complex and filled with witty lyrics, giving both performers showcase numbers to show off their Sondheim-worthy chops — in particular, Cathy's funny, vocally acrobatic audition song "Climbing Uphill" that last night got a special ovation from the audience for Seibert's rendition; and Jamie's Jewish fable number "The Schmuel Song" in which Resnick proved some Patinkin-esque prowess for manically sung storytelling. Both are very talented singers, though Resnick stands out a bit for his versatility, and a voice that blends pop range and cabaret power.

Sadly, though, for the emotional arc of the play, we get so few opportunities to hear the two lovers sing with each other — they are almost always occupying opposite sides of the stage, experiencing similar moments separately, sometimes singing directly to each other when the other one isn't even there. They even take a boat ride in Central Park at the heart of the show, where their backwards and forward narratives cross, during the number "The Next Ten Minutes" barely looking at each other, each in the boat by themselves at one point, and only harmonizing once. Their constant separation, and the lack of any moments, dramatically or musically, in which you're ever meant to feel the depth or sincerity of their love for each other leaves the audience mostly having to take their word for it, often in a minor key. This doesn't seem to be a fault of Berresse's direction but rather the tricky structure of the show itself, and something vaguely un-empathetic about the writing, particularly from Cathy's side of things.

The spare and soft-edged set by Tim Mackabee, composed primarily of geometric panels that are lit throughout with solid colors and sunset gradations, is crowned, literally, with a pretty, suspended doughnut of what look like dried white roses. The elaborate focal point above the stage plays a pivotal role in the finale, which Berresse admits he tweaked from the script in order to cast a more positive life on the dissolution of a relationship, and it adds a suggestion of the organic while also being a metaphor of its own.

As the friend I was with last night pointed out, and as I invoked in the review of If/Then last fall, there's a comparison to be made (that no doubt Brown was aware of) with Sondheim's famously difficult Merrily We Roll Along, a musical that begins in sorrow, with three friends having grown apart and lost the promise they had in their youth, and proceeds backwards to the joyous, hopeful early days of their friendship when they were three ambitious kids meeting in New York. Here, though, the sorrowful opening number can't hold a candle to the brilliant overture or the rollicking, albeit anger-filled opening party scene of Merrily, which led me to think there's an important lesson here — just because you open at the end of the story, and that end may be a sad one, it is still an opening number, and if it doesn't grab the audience and instead pummels them with defeat, you've made a grave error. This ain't opera, after all.

Certainly, though, there's plenty to admire in the experiment itself, not to mention the performances in this production, and ACT could have done far worse for a show to close the season at the Geary Theater. The Last Five Years is, without a doubt, a musical for and about the 21st century, and like a lot of contemporary stories, it refuses to go down easy.

The Last Five Years plays through June 5, pending any extensions. Find tickets here.