Intense emotions and rueful revelations abound in Antagonyms, the world premiere of a play by Rachel Gluck, a member of the Curio Theatre Company, now performing it in West Philadelphia.

We hear, painfully uttered and received with difficulty, Charlotte (Alle Spadino) tell Dorian (Alexander Scott Rioh), "I want to know you." But just how much tolerance will she have for the answer when she, her current paramour, her former flame Jonny (Andrew Carroll), and his girlfriend Mauve (Colleen Hughes) have a hard time fathoming even themselves?

Set in Philadelphia, the play finds this foursome -- with Jonny as an artist poised for a breakthrough or a breakdown and Mauve as his supportive yet somewhat languid lover -- exploring the limits of resolve and the reach of regret.

Past hinders present. Jonny, whose urges are wrapped up in persistent feelings for Charlotte, and Mauve, sister of hedonistic Dorian who has recently returned to her life in the midst of a transgender journey, struggle to reconcile their missteps, and they tie too much of their self-estimates to others' assessments of them. When the first act concludes, we feel drawn to Charlotte for her sensual and intellectual magnetism, and to Dorian for his carefree, even occasionally caustic, confidence. Yet we are perplexed by the other couple's stagnancy.

Nurturing destructive impulses and craving the abandon of Charlotte and Dorian, with Dorian proving an incendiary source of inspiration, Jonny begins to turn away from Mauve in favor of asking, "What else is out there in the world?" Charlotte captivates him, and Gluck, with Jack Tamburri directing, gives the two an amazingly bare scene in which a tortured Jonny reveals his deep addiction to Charlotte, his irresistible drug.

The playwright also masterfully addresses self-tolerance. Charlotte and Dorian appear to have robust amounts of it, but Jonny and Mauve -- with Hughes evoking sympathy as she parts from both her beau and her carefully guarded composure -- are harder to read and more complex. Although immensely wounded, they possess a grander sense of the reparations they must try to make.

The complexity of Jonny's choices drives the second half of the plot and leads us to ponder the power of love, lust, loss, and sorrow. Antagonyms, the fifth new work Curio has staged in its 12-year existence, will appeal to fans of both noir and grammar: Its title refers to words whose multiple definitions have contrary applications, such as sanction, which means to permit but also to penalize. After a tense exchange with Charlotte, Dorian uses another when saying that it's time he left, which could refer to fleeing or considering what remains. When patrons have left their seats, Antagonyms has left them with plenty to consider about their willingness to forgive themselves and to encourage the same in others.