Playwright Gina Gionfriddo has a lot to say in “Becky Shaw,” but much of it has been said before. People are complicated? Check. Relationships are challenging? Check. Some people are very perceptive about others – but about themselves, not so much? Check. The past is always with us, mucking up the present and casting clouds over the future? Check and double check.

A preponderance of the first act is devoted to backstory as the two main characters, a woman and her stepbrother, join their mother in a discussion of family history. We do learn certain things about them. Max, the brother, is a financial adviser: He tells people what to do with their money; Suzanna, the sister, is working toward a doctorate in psychology: She tells people what to do with their lives. And just a few months after her husband’s death, Susan, the mother (Dorry Peltyn), has taken up with a questionable lover who never appears onstage.

To their very great credit, director Phil Powers and his Performance Network cast deliver a first-rate production. And to the playwright’s credit, “Becky Shaw” has garnered a certain amount of acclaim, including being a finalist for the Pulitzer Prize for drama in 2009 (Lynn Nottage’s “Ruined” took the prize).

And the script takes welcome steps into the present as it becomes evident that Max (David Wolber) and Suzanna (Sarab Kamoo) share an affection that goes beyond siblinghood, and things really get off the ground with the arrival of the title character. Becky Shaw (Maggie Meyer) works for Suzanna’s husband, Andrew (Keith Kalinowski), whose interest may be more than collegial. He and Suzanna have set up a blind date between Becky and Max, a situation fraught with difficulties for all four of them.

Becky’s own life may be a mess – she’s broke, she dropped out of Brown University, her family doesn’t speak to her – but she offers keen insights into things troubling Max, Suzanna, Susan and Andrew.

And Gionfriddo gives Becky one of the all-time great second-act opening lines: “Something bad happened on my date with Max.” Nothing more will be disclosed here.

Meyer plays Becky as someone for whom a good hug and a little appreciation would do wonders. Andrew is an inveterate rescuer of wounded women, and Kalinowski imbues him with grace. Mom Susan is discomfited by the death of her husband and the disappearance of her settled life; Peltyn conveys a powerful sense of loss, discomfort and resentment.

Kamoo and Wolber have the most to do and they provide rich and vibrant performances. Kamoo is often in motion; Suzanna has many lines, and the movement keeps her from being static. While Max maintains a tighter, almost pathological, rein on his emotions (except when he doesn’t), Wolber lets us know there’s a real person in there.

Monika Essen’s sets – a series of large photographs denoting various indoor locales behind a few pieces of furniture – supply strong visual engagement, and her costumes are so precisely what the characters would wear that I almost forgot to mention them.