Korea’s storied, and sometimes traumatic past, provides cinematic power once again for YMCA Baseball Team (2002) and C'est Si Bon (2015) director Kim Hyun-seok. Also assistant director on The Isle (2000) and screenwriter for Joint Security Area (2000), Kim has an uncanny skill for taking the nation’s scar tissue and fleshing out poignant films.

It would violate our no-spoiler guidelines to reveal exactly which historical national horror forms the basis of the final act in I Can Speak, but it certainly signals a neck-breaking U-turn on the film’s earlier pitch and tone.

That is established through the odd couple pairing of Nah Ok-Bun (Na Moon-hee – Crying Fist, You Are My Sunshine, Cruel Winter Blues) and Park Min-jae (Lee Je-hoon – Bleak Night, My Paparotti). The latter is a cantankerous retiree who occupies herself by filing endless petty complaints at her district office, earning her the nickname of ‘Goblin Granny’. The former is young, super smart, ambitious and newly recruited to the district office, where he soon learns the steep demands of dealing with Ok-Bun’s endless complaints.

While these two seem destined to clash, their paths cross when Ok-Bun, who wants to learn English, realises that Min-jae has a superb grasp of the language and implores him to teach her.

While Min-jae initially refuses to take on this troublesome student, when he sees Ok-Bun’s kind-heartedness towards his younger brother Young Jae, he decides to start teaching her. As her motivation for learning English emerges, we learn more about Ok-Bun’s tragic past and how she will need Min-jae’s further support in the long battle for justice.

The off-kilter laughs of the first half are then replaced by the heavy dramatic battles of the second part. How we see Ok-Bun – seemingly the worst of neighbours to have – changes dramatically. It stresses the importance of understanding the journey someone has undertaken before we judge them too soon.

The film’s title moves well beyond the straightforward notion of learning to speak in another nation’s tongue. It is also about an entire nation getting its voice. How Koreans have been treated by other major nations in the past and how it can have its voice heard – with the international popularity of Korean cinema itself offering such a voice.

The chemistry between Na Moon-hee and Park Min-jae is essential in the grandmother-grandson-like relationship that builds between them. For the odd couple pairing to work on screen, those performances must succeed in welding them together.

It is difficult to unpack much further why I Can Speak is such a vital film, except to add that the historical issue it highlights remains a live topic. An injustice that has yet to be righted.

We will leave you blind to any further details of that ahead of watching, but that heady cocktail of laughter, crying, historically profound but currently important areas all converge in Kim Hyun-seok’s truly important film.