With their recent collaboration with Sarah Gancher and Anne Kauffman, Abigail and Shaun Bengson (“The Bengsons”) have redefined the meaning of the theatrical convention of the musical. Without elaborate sets, costumes, large ensembles of singers and dancers, and multi-million-dollar budgets, The Bengsons have successfully mounted a stunning musical with a believable story and a brilliantly executed score. “Hundred Days,” currently running at New York Theatre Workshop, is a musical with heart, hope, and a hundred days of pure love that often brings the audience to a shattering stillness.

After a traumatic event in Abigail’s life when she was fifteen, she finds it hard to trust in the future or to trust in the longevity of significant relationships. This “character trait” is affirmed in recurring dreams about the premature death of a loved one that interferes with Abigail’s full commitment to Shaun. How their relationship develops over the contracted period of a hundred days, and how they managed to stay together for ten years is the compelling story behind “Hundred Days.” By making the decision to develop the “theatrical imagining” about a fictional couple (Will and Sarah) by placing their own love story at the piece’s core, Abigail and Shaun have created a compelling musical treatise about the power of love.

The musical begins with the affirmation of The Bengsons’s status as a married couple (not brother and sister) with the song “Vows” – their wedding vows: “All my life I’ve been looking for you Been looking for you/Take my pride and lay it at your feet/A woven mat to keep you.” The balance of the musical is retrospective of their relationship from their first meeting “at the first rehearsal of a massive anti-folk folk-punk old-timey neo soul band” the year after Shaun moved to New York City to their marriage. Each song in that “history” is the perfect balance of pathos, ethos, and logos easily persuading the listener of the depth of the authenticity of their unconditional and non-judgmental love.

After finding Abigail, Shaun follows her suggestion – “Let’s eat” – and they end up in a diner where Shaun “suddenly feels like he knows her. Like time is bending back on itself” and where Abigail recalls, “It was like every door of my body opened and he just wandered in.” Abigail breaks up with her boyfriend and Shaun “breaks up” with his friend Max (“God Can Be a City Boy”) and their journey begins. The Bengsons’s music is eclectic, unique in tone and its rich thematic synchronicity pervades every song and every space between the songs – songs that celebrate sadness, joy, separation, reconciliation, and redemption with a deep and rich spirituality. “Hundred Days” transcends musical theatre where actors play instruments on stage. “Hundred Days” is a musical featuring a band on stage with its members performing a fully developed musical with a beginning, middle, and end.

The show’s songs continue to explore the growth of the relationship between Abigail and Shaun with a mix of rock, blues, and jazz. Sometimes Abigail and Shaun sing solos, sometimes duets, sometimes with the other performers. And sometimes Jo and Reggie sing solos that provide exposition. The styling and staging here are unique and deeply persuasive.

It is difficult to categorize Abigail’s performance of the standout number “Three Legged Dog” except to affirm that Janis Joplin was “somewhere in the house.” Abigail rehearses the haunting possibility of losing Shaun and how she will “survive” his loss: “When you go my shards will scatter/Half of me is dying too.” In what might be the climax of the musical, she decides to leave. Shaun immediately begins to search for her, singing: “I thought god was a friend/Who would help make things easier/I thought time was/On my side/I thought love was supposed/To make things easier/Now love is/A long goodbye.”

The conversation (“Transcription”) that follows is a prolonged dialogue between Alison and Shaun during which they share their fears and hopes about aging and the vicissitudes of life and look forward to becoming “other stuff together” and overcome Abigail’s concern “That everyone [she loves] gets sick or dies or goes mad” by embracing the inevitability of aging and death. After the sharing, they decide to get married “in real life.”

The show’s final number “Bells” is the first song Abigail and Shaun wrote together: it was written for Abigail to sing after Shaun “is gone.” The lyrics and music are both haunting and life-affirming: “I can sing Gloria/the lights over Astoria/I know you are alone/I know you can’t come home. The musical ends with the couple affirming to “say yes to sickness; to say yes to health; to say yes to riches and to brokenness.” They say yes to the future, to futility, to trying, and yes to death doing us part” affirming “What else can we do?”

The “Family Band” is without comparison: the members not only excel in performance on keyboard, guitar, drums and percussion, cello, and accordion; they also act, sing, and move with “triple threat” persuasiveness. Colette Alexander, Jo Lampert, Dani Markham, and Reggie D. White join Abigail and Shaun in this marathon of a new musical. The creative team of Kris Stone, Sydney Gallas, Andrew Hungerford, Nicholas Pope, and Lindsey Turteltaub create a space where The Bengsons create magic and transcend all expectations set by traditional musical theatre. Sonya Tayeh’s movement direction creates exquisite images throughout the performance.

“Hundred Days” celebrates Saying ‘yes’ to life and all its uncertainties: celebrates facing the fear of loneliness, rejection, and being able to take each other’s troubles “into” each other. It is an event not to be missed and will certainly have a life beyond this iteration at the iconic New York Theatre Workshop.