Canadian playwright Jordan Tannahill puts together two things in Late Company that should never mix: dinner parties and grief.

There are two families. The hosts, whose son Joel committed suicide, and a couple and their son, Curtis, who bullied Joel with his friends. The unsettling drama that ensues asks who or what is to blame for the death of this boy. The conversation flames into anger and distress. It continues beyond the point – if I was anyone else in the room, I would have left.

You’re hooked by the question: why are these two families having dinner together? Is it about forgiveness? Forging friendship in difficult circumstances? Solidarity? A feeling of obligation?

So far, so topical.

Deborah and Michael – Joel’s parents – are broken apart by their son’s death. Todd Boyce provides Michael with a Canadian version of stiff upper lip smoothing through the process of the dinner party like an unwelcome canvassing stop on one of his political campaigns. Lucy Robinson’s Deborah is bitter, righteous, and lonely. She cries alone with little support from her husband and her description of finding her son is heartbreaking. For that, she has the audience’s every sympathy, but her self-righteousness never quite seems justified. It’s left unclear whether it is Deborah’s grief speaking or her character when she descends into cruel words of retribution against Curtis.

David Leopald is perfectly cast (though not quite believably sixteen) as the high-school bully playing Curtis with moody indifference and questionable sincerity. His mother Tamara (Lisa Stevenson) tends to shriek her sentences with all the force of love, positivity, and empathy she believes in. Stevenson is brilliantly irritating in the role of all-smiles high school sports mom. Her husband Bill (Alex Lowe) has a tough love approach; at one point smacking his son around the head for an unwise word. All five performances are utterly convicting.

The play tries hard to plot out the factors leading to a teen boy’s suicide – everything is considered – mental health, parental lack of support, his sexuality, online bullying, his own pitch to be ‘weird’, the school, and the parents of the bullies. It’s good that we are left without answers. This isn’t a subject that can have a neat conclusion like an Agatha Christie crime drama.

More could have been done with the design to highlight both boys’ online antics. In a play that purports to be about cyber bullying, the digital experience of the play was all talk and no representation. It’s probably a matter of budget but if these boys could’ve been making videos in their bedrooms, surely this play could have filmed something too.

A moment that is meant to be an emotional high point of the play, when Michael and Deborah watch a video of Joel parodying a chart song, was lost on me. I was sat in one of the few seats around the stage that could see the laptop screen and the video seemed to be a strange gif of a boy wiggling his arms rather than the belted song with hilarious dance moves that the parents’ reactions described.

Michael Yale’s careful production is nonetheless a brilliantly depicted world of parenting teens, the loss of a child, and a bully’s regrets.

Late Company is playing at the Finborough Theatre until 20 May.