Pat Proft remembers the day in 1965 when he and fellow actor Mike McManus drove to work at the Brave New Workshop, which Dudley Riggs had established in his coffeehouse on E. Hennepin Avenue in Minneapolis. But as Proft and McManus pulled up that day, they noticed a sign that said the theater had moved.

"We thought everyone was kidding the week before when they said we were moving," Proft said. "But there was a sign on a flattened-out cardboard box that said, 'We have moved' and it gave the new address. So we drove over to the new address and Dudley says to us, 'Welcome to your new theater.'"

Ever since (save a short sojourn in Calhoun Square), the Brave New Workshop has built its legend in the quirky little storefront at 2605 Hennepin Av. S., a theatrical landmark in Uptown Minneapolis. Proft found his legs as a brilliant physical comedian there; Al Franken and Tom Davis honed their stand-up chops; dozens of writers and actors worked their way through the workshop before taking off for the coast.

Proft expects pangs of nostalgia during the run of "Obama Mia!" which opens Friday as the workshop's final main-stage comedy revue at the fabled address. This fall, the troupe will open a new stage at 824 Hennepin Av. S. (interesting how they've always stayed on Hennepin), the downtown location best known as the former home of Hey City Theater.

"I know why they're moving, and it's a good idea," Proft said. "But if I were ever going to do a show again, I would do it there, in that room."

The workshop is keeping its lease at 2605 Hennepin. It will become "Brave New Workshop: Student Union," allowing more space for an improv school that has grown to nearly 250 clients. Students will use that stage for their shows.

Dudley Riggs, who sold the business in 1997 but still attends opening nights, said he has great affection for the building -- despite (or perhaps because of) its foibles.

"I was thinking today about how it was just a couple of years ago that Tom Sherohman and I were up on the roof, plugging leaks," Riggs said. "The building has a certain familiarity, and we get seduced by the familiar."

Proft, with a reputation burnished by his Hollywood screenwriting success ("Naked Gun," "Police Squad," "Hot Shots!"), can afford to get misty as "Obama Mia!" rolls along this summer. Current artistic director Caleb McEwen and owner John Sweeney don't have that luxury. They deal daily with the leaky roof, the crowded auditorium, the dodgy air conditioning and the dangerously cramped backstage. McEwen doesn't have time to cry. He's trying to get a show ready; Sweeney has his dry eyes on the future.

"It doesn't seem like a last show," Sweeney said. "It's a transition. We're still going to be just as busy here."

Sweeney and his wife, Jenni Lilledahl, bought the business from Riggs in 1997, and within a year moved mainstage shows to Calhoun Square. The experiment lasted three years, and by 2001, everything was back at 2605 Hennepin. You need not remind Sweeney and McEwen that Calhoun Square turned out not to be such a great idea. But they point to the wisdom gained from hard knocks.

"This seems different," said Sweeney. "First of all, this time we bought the place. We own it, so if we decide to leave, we need to find someone to replace us. We can't just leave it.

"Second, we bought a theater this time. At Calhoun Square, we thought we could shove a theater into the second floor of a shopping mall. The layout at 824 Hennepin is almost identical to this. It's a theater."

Riggs has one caution about the workshop's decision to plant a flag downtown and still keep 2605 Hennepin running. As he learned when he opened the Dudley Riggs ETC theater on the West Bank in the 1960s, "When you have two locations, you compete with yourself."

McEwen's enthusiasm is mostly about the artistic possibilities in the new space. A wider stage, better lighting and technical capacity, fiber optics and a green-screen video room all offer opportunities that the workshop has never enjoyed.

"And there isn't water running down the wall every time it rains," he said.

I hate goodbyes

McEwen feels the workshop has been about the people, not the facility. He does admit, though, that perhaps as "Obama Mia!" winds down, he might reflect on it all.

"I will miss the great sense of history," he said. "That is worth something."

Indeed it is. Proft will recall the night Jim Hudson stood up and broke a hole in the ceiling with his head -- and kept right on talking. That hole is still there. Proft will also remember doing the moon-man skit with Ron Douglas, both of them wearing stools as spacesuits, and studying audience members; and he still talks of the first time he tried his pickpocket bit and ended up shredding Sherohman's pants.

"That's my favorite bit that we ever did," he said.

Sweeney is sensitive to that history, too, recalling his first day on the job in October 1993. It's one reason he wants to keep his lease on the building and push forward with 2605 Hennepin as the improv school.

"We want to keep this space going," he said, "so students can say, 'I did my first show on the same stage where Pat Proft cut his teeth.'"