“Bright Half Life,” the sweeping story of lesbian soul mates, spans 45 years in little more than 60 minutes, which is a lot to keep track of if you’re an actor. So the company put up a timeline on the wall of the rehearsal room.

"It’s this brilliant thing we can refer to," says actor Maureen Porter, pointing to pictures on the timeline showing news events that the play references, like the Challenger explosion and the passage of gay marriage. "We come and say, 'what was happening in 2004 and what was the context for Vicky and Erica in their relationship?'"

Written by Portland-grown playwright Tanya Barfield, "Bright Half Life" runs at Profile Theatre Oct. 27–Nov. 13. [Hear Barfield discuss the play in State of Wonder's guest curator episode with her.]

Not only does the play follow these two lovers as they orbit each other for 45 years — through falling in love, two proposals, kids, divorce, joint custody — but it’s constantly shifting in time. In a matter of minutes, the scenes bounce from, say, signing the divorce papers, back to the couple's very first night together, then forward to navigating joint custody, and then back again to the kids' birth.

If that sounds confusing to watch, think about what it’s like for the actors to memorize and keep straight.

"It's a funny thing," says actor Chantal DeGroat, who plays Vicky, a successful, type-A businesswoman from a traditional family. "Some of these scenes repeat in the play, and come in and out, and sometimes it's just a fragment of the scene that will come back again. And so we'll be in one moment, and then realize this scene is done here, and we're flipping into this other thing for three lines, and then we're back out again."

With little more than a bare set, the actors have to signal each jump in time through changes in their tone and movement, with help from a slight change in the lights.

Challenging as it is, though, DeGroat and co-star Maureen Porter see the zigzagging narrative as mirroring the way memory works in real life: one memory leads to another, with no respect for chronology.

"As we’re working, we’re finding all the threads of what connects one memory to the next and why some of them repeat," says DeGroat. "So maybe we're having a conversation, and the words we're using are one thing. But you and I, as the people in the relationship, know we're talking about this incident from before — so decoding what it is we are really talking about, and saying, 'Oh, it’s just like the moment with the Gorgonzola!' It's just like that moment between them again."

"She's mapped it in a way that's remarkable," agrees Porter, "and it feels very much like a kind of duet."

Many of Barfield’s plays sparkle like this. They don’t seem like they should work on paper, but somehow they forge an aching emotional realism by abandoning theater’s conventional rules for realism.

"We all have those moments where history is suddenly present with us in this moment, and the things that we are thinking about for the future are present — and the ways in which those combine to make every moment feel both familiar and new is remarkable," says Porter. "She’s written that. It feels very much like a real relationship."