Who is Augusta Hope’s “other half”? In Glen’s debut, shortlisted for the Costa first novel prize, at first it’s Augusta’s twin sister, although the differences between them become more marked as time passes. A paid-up member of the awkward squad, from an early age Augusta is obsessed with words – too clever by half for her smallminded parents (who seem to belong to the 1950s rather than the present), and miserably out of kilter with everyone else.

One of Augusta’s favourite words is “Burundi”, for the sound of it, but she also learns all she can about the distant African state. Alternating with the chapters she narrates are those in the voice of Parfait, a boy growing up in Burundi and facing horrors of a different magnitude altogether.

While one can guess where the narrative is heading from fairly early on, there is pleasure in seeing how skilfully the two threads are brought together. The great sadnesses that threaten to overwhelm both Augusta and Parfait lend a wistfulness to the novel that holds any mawkishness in check: this is a therapeutic dose of high-strength emotion.

• The Other Half of Augusta Hope is published by Borough (RRP £8.99). To order a copy go to guardianbookshop.com. Free UK p&p over £15.