"Mesa" is particularly personal for playwright Doug Curtis and his wife and frequent collaborator, Heather Moore.

The play, which Invisible Theatre opens next week, is based on a trip Curtis took from their Calgary home with Moore's grandfather. "My mother-in-law asked me if I would like to drive Grandpa Bud to Mesa," Curtis said of that day in 1998.

Flying Grandpa Bud down wasn't an option.

"He was 93 and he wanted his car there," says Curtis in a phone interview.

"Next thing I knew, I was packing my stuff. We loaded the car, and we took about five days to get there."

Those five days became the play, which has been seen across Canada but is making its U.S. debut with IT.

In "Mesa," the younger man, Paul, is eager to explore the back roads to Arizona.

Grandpa Bud just wants to get there, via the interstate. Denny's was his choice for dining.

He's anxious, you see, because the widower has a new gal who plans to be in Mesa with him. That is, if her hip operation doesn't get in the way. And he has lots of friends who hang out together and cut a rug at the Saturday night dances.

The two clash over bedtimes, side trips, the music they listen to.

That trip gave Curtis lots of material. But it also gave him a deep respect for Grandpa Bud.

"This is a love story between two men," says the playwright's note in the script.

"They just happen to have 60 years difference between them."

The play "is a very detailed painting of what that (trip) was like," says Curtis.

"As we bombed across the Montana flatlands, I had the eureka moment: two men trying to get to Mesa."

While much of the story is real, as are most of the people, "Mesa" wasn't an attempt to catch the goings-on during the trip as much as to catch the spirit of Grandpa Bud and his generation.

"They worked hard, saved money, and when they retired they played like children," said Moore.

"My grandfather's generation made an effort to get to know each other. They didn't have phones or email. The Saturday night dance was their Facebook. We've lost that (personal contact), and that's an important part of the journey."

When Curtis decided to write the play, Grandpa Bud was all for being the center of a theater piece.

"Oh, yeah," he said to him. "It's about time."

Grandpa Bud passed away in 2002, but he got to see the play's 2000 premiere, which fell on his 94th birthday.

He was pleased. "He said, 'I thought the actor who played me was quite good,' " recalls Moore.

While "Mesa" centers on two people, the story goes beyond that.

"It's about community," says Moore.

"It says life is short," adds Curtis, "so make it sweet."

If you go

• What: Invisible Theatre's production of "Mesa."

• Playwright: Doug Curtis.

• Director: Harold Dixon.

• When: Previews 7:30 p.m. Tuesday; opening is 7:30 p.m. Wednesday. Regular performances are 7:30 p.m. Wednesdays and Thursdays; 8 p.m. Fridays and Saturdays; and 3 p.m. Sundays through Dec. 2. No show on Nov. 22, Thanksgiving.

• Tickets: Preview $18; regular performances, $28. Tickets are half-price 30 minutes before curtain, subject to availability.

• Reservations/information: 882-9721, invisibletheatre.com