The considerable charm of Miriam Toews’ fiction comes, in part, from her ability to create characters in situations of long-term duress with a brilliantly emulsified mix of repression and humour, punctuated by bursts of real emotion. In this, her first novel since nabbing the Governor General’s Award for A Complicated Kindness, Toews’ unsunny topic is mental illness – something on the periphery of, but never so solidly confronted in, her previous work.

Here, Hattie Troutman finds herself returning to Winnipeg from Paris to assume guardianship of her niece and nephew, Thebes and Logan, following the mental collapse of her sister, Min. Having been freshly jilted by her French lover, Hattie is in a tenuous emotional state herself, but ripe for change and used to picking up the pieces when Min falls off the rails.

Shortly after Hattie’s arrival, a suicidal Min is hospitalized. Desperately in need of a game plan, Hattie impulsively takes the kids on the road to find their father, Cherkis, who was banished from his home years ago by a raving Min and who now lives somewhere in the western U.S. Travel is a natural portal to memory, and here it is used effectively as a segue into Min and Hattie’s complex past. What emerges is a portrait of a sibling relationship dictated by equal parts love, dependency, and disease. In other words, it’s a deeply problematic relationship, but one not easily dismissed.

Familiar elements from Toews’ previous novels – the road trip, missing parents, a story told in hindsight, teenagers suddenly thrust to the helm – recombine effortlessly here. The journey at the novel’s centre gives the narrative a momentum wholly absent in A Complicated Kindness, which dealt with the suffocating, static atmosphere of a Mennonite community. And Toews is now an old hand at writing the kind of precocious teenage dialogue, with its flatly ironic tone, that made the movie Juno seem like a revelation to so many last year.

This is a book that builds its complexity so subtly and imperceptibly that the inevitable sense of deep engagement feels almost like sleight of hand.