A 25-foot fibreglass model of a shark — or its rear half, at least — adorning the roof of an otherwise ordinary terraced house in suburban Oxford, England, the Headington Shark is the kind of local curiosity that makes any casual passersby think, “There must be a story there.” And there is: It’s a work of protest art devised in 1986 by sculptor John Buckley and homeowner Bill Heine as a statement against nuclear warfare and military airstrikes. Forty years later, however, “Learning to Breathe Under Water” imagines quite a different one, taking the eccentric artwork as the starting point for a fictional tale of grief, healing and household repair, and as the visual cue for its own eccentric stylistic flourishes. If the real-life shark sculpture was a controversial point of community debate, however, Rebekah Fortune‘s highly likable, heart-on-sleeve tearjerker won’t be nearly as divisive.

Warmly received at Karlovy Vary — where it premiered in the Special Screenings sidebar — “Learning to Breathe Under Water” should continue to please crowds on the festival circuit before being scooped up by indie distributors with an eye for offbeat but audience-friendly (and indeed family-friendly) fare. Sympathetic turns from Oscar nominee Maria Bakalova and BAFTA nominee Rory Kinnear will help raise the film’s profile, though its best performance comes from 11-year-old Irish actor Ezra Carlisle (recently seen in “Hokum”), who’s immensely appealing but never cloying as our gravely earnest, often accidentally funny protagonist and narrator.