In American Sign Language, the word for "lover" is made up from two gestures. The first is for "love." The second is for "person." It's the same nomenclature used for a person's occupation. In other words, being a lover is a job.

And like any job, it's hard work, as is proved in Aditi Brennan Kapil's "Love Person," a deep and moving meditation on relationships and communication now running in a sharp new production at Park Square Theatre.

Since its debut in 2008 at Mixed Blood, "Love Person" has been produced around the country. Kapil's playwriting career has also taken off, but her debut shows that favorite themes and a genuine theatrical playfulness were present from the start. Here, Kapil the playwright gets an assist from Kapil the director, who makes the most of Park Square's size to illustrate the distances our quartet of characters often feel.

The show centers on Free and Maggie, a long-standing couple who are encountering rapids in their relationship. Free is deaf and speaks only through ASL. Maggie teaches poetry and her ability to hear gives her access to a world that Free feels that she can't join.

Free's sister, Vic, has been a longtime loser in love, but has her eyes on a shy Sanskrit scholar, Ram, who is working on translating ancient Indian love poems After spending a week with Vic, Ram heads back home, figuring their brief fling is over.

One night, angry with her own relationship, Free sends Ram an e-mail. This opens a new relationship, as Ram feels much more comfortable communicating by post than in person. He also thinks it is Vic trading messages. Ram is falling in love, but not necessarily with whom he thinks.

After a clumsy opening scene where Ram lays out the play's themes a little too much on the nose, Kapil's script finds its footing. This often happens in silence, as Free and Maggie talk in sign, or as Free and Ram trade e-mails. It's a silence that is absolutely absorbing (and handy supertitles keep the audience up to date on the action).

The solid company is led by Canae Weiss as Free. Weiss uses both broad gestures when communicating with sign and subtler expressions when silent to let us into the character's cauldron of anger and fear.

Erin Anderson Gardner matches Weiss as Maggie. The character is squeezed by the story and by her life in two worlds. Gardner expertly explores both halves, as she offers us a complex look at a woman who can't understand where her relationship went wrong.

The careful, well-built performances extend to Elizabeth Efteland (Vic) and Imran Sheikh (Ram), who fill out the play's unusual love quadrangle.

Ed Huyck writes about theater.