Provided.

In some performances, the characters that never appear onstage are just as important as the ones who do.

This is the case for the Great Canadian Theatre Company’s season opener, the world premiere of The Boy in the Moon.

The play is based on journalist Ian Brown’s Globe and Mail essay series, and memoir of the same title. Brown and his wife Johanna Schneller spent a decade raising their son Walker, the titular boy, who was born with a debilitating genetic mutation called cardio-facio-cutaneous syndrome (CFC). Walker, who eats through a feeding tube and cannot speak, is largely an unseen presence in the stage version, only appearing in sketches projected on the back wall of the stage.

In a sequence that repeats several times throughout the play both parents ask each other the questions they wish their son could answer.

“How do you think without words?” they wonder. “Do you like your life?” These questions of consciousness and identity are at the heart of the production.

Artistic director Eric Coates said he has been left to ponder “the value of a life that can’t communicate,” while working on the production.

He said the main challenge has been building a performance around Walker’s absence.

Actors Peter Haworth and Manon St. Jules take on the roles of Walker’s parents and actor Marion Day frequently enters and exits the scene as Walker’s sister Haley, his nanny Olga, and a series of medical specialists.

Together the three performers create a monologue and dialogue-heavy philosophically meandering memoir onstage detailing the exhausting years Johanna and Ian spent raising Walker and pondering their love for him and value of his life.

“This is an extremely challenging play,” Coates said. “It doesn’t have any kind of conventional dramatic structure.”

Specific lines about Walker’s “off-shaped head, in his jumped-up heart,” lose their intimate power in the transition from the pages of Brown’s memoir to the stage. Others are brought to life in a more visceral way through live performance.

“Once he bit his hand to the bone,” Johanna says recalling Walker’s propensity for self-injury and the audience reaction to this anecdote is palpable. Everyone gasps.

The parents re-enact nights of feeding Walker, of stopping him from punching himself in the head, or taking him on hellish trips to the hospital, and no one seems to know whether or not it’s safe to laugh.

In a particularly haunting monologue Brown describes the suicide fantasy he had when his son was still very young. He imagines taking Walker out into the Canadian North and the two of them freezing to death together.

“The thought of the fucking nightmare of getting Walker through an airport with ski equipment,” was always enough to dissuade him though, he concludes.

It’s this kind of dark humour and honesty that elevates this sparse, dialogue-heavy performance. It might not be particularly theatrical materiel, but it isn’t trite or dull.

“I despise inspirational memoirs,” Johanna Schneller says near the end of the performance.

Ten minutes later, as people shuffle out of the theatre, murmurs of “what an inspiring story,” fill the theatre anyway. Everyone is momentarily incapable of irony.