One of the most isolated Indigenous people on Earth, the Sentinelese of India’s North Sentinel Island remain a mystery to anthropologists. For evangelical Christian groups, however, these so-called “unreached” tribes represent a challenge – and a calling. Through illicit means, 26-year-old American missionary John Chau approached the island in 2018 with gifts and Bible verses. The Sentinelese responded with a hail of arrows, killing the young man. The incident made international headlines, with Chau’s death prompting a flurry of reactions ranging from claims of martyrdom to mocking memes. Diving into the heart of the puzzle, Amanda McBaine and Jesse Moss’s documentary strives to contextualise – and empathise – with Chau’s gruesome end.

Read out by actors, excerpts from Chau’s diary and a letter from Chau’s father illuminate the circumstances that spurred his quest. Wholly immersed in a Christian and evangelical education, Chau was also transfixed by colonial adventure stories. His near decade-long preparation for the fatal journey includes him learning survival skills and getting training in emergency medicine. He even joined a missionary bootcamp where facilitators would act the roles of hostile tribespeople.

Interviews with failed missionaries and expert anthropologists, however, reveal the futility, the recklessness, and the arrogance of Chau’s endeavour. Produced under the banner of the documentary arm of National Geographic, The Mission even uses the channel own’s archival works to allude to media complicity in perpetuating exotic imagery of indigenous lives. Yet the film also suffers from similar missteps. Though effective in filling in the gaps of Chau’s story, the impressionistic animation dramatising his final moments commits a similar sin as the swashbuckling tales of yore, and makes a spectacle out of a tragedy that is ultimately not all that mysterious or abstract – but in fact grounded in material sociopolitical contexts.

• The Mission is released on 17 November in UK and Irish cinemas.