Things change when you get older.

Just look at Tomorrow, the latest theatrical meditation from Vanishing Point, which plays its only Scottish dates at Tramway from this weekend following its premiere in Brighton and follow-up dates in Brazil.

In the company's Glasgow rehearsal room, a largely youngish cast from Scotland, England, Russia and Brazil convene under director Matthew Lenton's guidance to go through a scene in what, despite only makeshift scenery, conjures up the slightly derelict feel of an old people's home.

As the cast assemble, their natural ebullience seems to slow as they ease into character. When they cover their faces with tight-fitting latex rubber masks, the transformation is complete. Only when one or other of them breaks into their natural stride do things jar. Otherwise, it's as if time itself has caught up with them in an instant.

"I was interested in doing something about care," says Lenton. "I had this image of a cast in their eighties or nineties, but to have one young actor hidden among them wearing this realistic age make-up like Kate Winslet had in Titanic when she became the old lady. I wanted to have this really slow piece of theatre where almost nothing happens, but then in the last 10 minutes one of them begins to do things that should be physically impossible for them to do.

"Then I had this idea of using a mask somehow, so we bought one to try it out in a development week, and it became apparent really quickly that, as good as masks are, as soon as you put them next to an old person on a stage, they're not convincing. Once we realised that wasn't going to work, I thought, well, let's reverse it, and see what happens if you have a young person in a mask, so the mask then takes on a much more metaphorical quality, because the audience can see what's happening, and you're asking them to buy into the metaphor, as they watch someone becoming old in an instant."

As Lenton explains himself, what he says becomes as close an approximation as you'll get to the instinctive nature of Vanishing Point's methodology, which occupies a dreamier, more magical-realist landscape than more straight-ahead theatre companies. Despite Lenton's observations too of Tomorrow as "a chamber piece, much more intimate than a lot of other stuff we've done lately, which has been big and visual," as the play lurches into other worlds, there are recognisable Vanishing Point tics that come through in a typically expansive co-production with Brighton Festival, Tramway and Cena Contemporanea in Brasilia in association with partners in Sao Paulo and Moscow as well as Platform in Easterhouse and the National Theatre Studio in London.

While several plays have looked at ageing over the last few years by way of the effects of alzheimer's disease and euthanasia, the subject has crept into Vanishing Point's other work almost subliminally. Both Interiors and Saturday Night have featured characters in need of care, while the second half of the company's last show, The Beautiful Cosmos of Ivor Cutler, focused more explicitly on the late poet and singer's fading health in his later years.

But beyond the aesthetics of Tomorrow, there there are some serious questions being asked in what sounds like a very personal work for Lenton.

"It's about who cares for people and how you care for them," he says, "and whether vocational care is better than care by nurses who do it for the money, and whether at the point of delivery whether one is any better than the other.

"That all comes from the simple idea that we'll all need care one day if we're lucky and we're not hit by a bus before then. There's not much choice in being cared for, because we'll all need it, but there's a much greater choice in deciding to care for someone, how you do that, and what limits it pushes you to as a carer.

"All of these ideas are rich to me in the piece, but I wanted them to be embedded, and I wanted the piece to be like a poem.

"I'm very interested in stuff these days which invites an audience to make their meaning for themselves, so we create something that has all these things in it, but an audience has to look for what they take out of it."

Tomorrow is at Tramway, Glasgow, from Friday to October 11.