Pennsylvania Shakespeare Festival has staged a near-perfect production of Jason Robert Brown’s complex and challenging musical “The Last Five Years,” through June 30 in the Schubert Theatre at the Labuda Center for the Performing Arts on the campus of DeSales University, Center Valley.

All the parts came together skillfully for a thoroughly satisfying and outstanding evening of musical theater.

This two-person, almost completely sung-through show is very demanding for the two leads and Benjamin Lurye and Chani Werely were up to the task as couple Jamie and Cathy with soaring vocals and crisp, smart acting.

The five person orchestra was on stage and on point. Brown’s music is not easy and Walter “Bobby” McCoy not only played the keyboard, but also conducted the other musicians (He also is music director!). The strings by cellist Audrey Simons and violinist Linda Kistler gave the show a lush feel while guitarist Mike Lorenz assisted McCoy with the lead lines and bassist Ty Hooker-Haring kept the rhythm. The orchestra also interacts with the two actors at several points to good effect.

The show follows the love story of the two New York artists over a five-year period. The conceit is that Cathy’s arc starts as the couple has broken up for good and progresses backwards chronologically, while Jamie’s arc starts as he has just fallen in love with Cathy. The two actors never interact until they meet in the middle at their wedding. It is a credit to the two actors abilities that they successfully convey the changes and emerging problems in the couple’s relationship, even though they must pantomime that the other person is there for most of the show.

The structure is a little unorthodox and could easily get confusing, but in director Jason King Jones’ deft hands, the story remains clear and cohesive. Jones’ attention to detail threads the story together as conversations one actor has in the beginning of the show are answered by the other later on.

As the show starts, Werely’s Cathy is painfully mourning the end of the couple’s relationship with the poignant “I’m Still Hurting,” while Lurye’s Jamie is humorously giddy as he sings “Shiksa Goddess.”

Werely follows up with the desperate “See I’m Smiling,” while Lurye is literally jumping on the furniture, in the dynamic “Moving Too Fast.” A fun highlight is Lurye running back to play a staccato chord on the keyboard, over McCoy’s shoulder.

Lurye’s “The Schmuel Song” in which he urges aspiring actor Cathy to follow her dreams, is sweet and heartfelt.

Werely ably conveys Cathy’s growing frustration and insecurity, as she attends cattle-call auditions in the clever “When You Come Home to Me,” and falls back on summer stock in “A Summer in Ohio.”

However as Cathy’s arc takes her to the wide-eyed first flush of love in “Goodbye Until Tomorrow,” Jamie is bitterly rehashing what went wrong in “I Could Never Rescue You.”

The whole piece is a fascinating dissection of the psychology of a relationship as it blooms and dies.

Costume director Jeannette Christensen’s meticulous designs, in the characters’ frequent costume changes, helps to maintain the characters’ place in time. The contemporary set by Charlie Calvert is stripped down and features a reflective floor, that looks like water, and suggests the fluidity of relationships.

Meet the actors for a talk-back after the shows June 20 and 27. There will be an audio described performance at 2 p.m. June 22.

The play contains mature themes and brief strong language and is recommended for age 13 and older.

Tickets are $51 to $70.

Performances are 7:30 p.m. June 12-24, 19-21, 26-28; 2 and 7:30 p.m. June 15, 22 and 29; 2 p.m. June 16, 23 and 30; and 6:30 p.m. June 18.

For information, call 610-282-9455, or go to pashakespeare.org/