The film follows Jesper (voiced by Jason Schwartzman), a spoiled and rich youth of privilege who's a cadet at a Royal Postal Academy. He's not doing much training, however; he would rather lounge on a divan in a tent on camp while being served espresso. Jesper wants nothing more than to live in his wealth, and purposefully fails his training to avoid doing work. But his father runs the Royal Postal Service and hits his son with a wake-up call: To make Jesper learn responsibility and work ethic, his father makes his son a postman and sends him to Smeerensburg, a secluded island cut off from the rest of the world. If he fails to establish a postal service and successfully send six thousand letters within a year, he'll be cut off from his inheritance.
The Royal Postal academy is surrounded by a sprawling, lusciously green landscape that reminded me of the forgotten Warner Brothers animated film, Quest for Camelot. By contrast, Smeerensburg is a bleak and cold place, with the dull tones of Mulan's wintery battle setting. Its homes, in the cramped, ramshackle style of Harry Potter's Hogsmead, look seemingly abandoned. But Jesper soon learns that he has walked into a town built on the generational violence of its two feuding families, the Ellingboes and the Krums (led by Joan Cusack sporting a kind of Yzma energy). It's chaos as Jesper tries to avoid the battle scrums. Hiding from the madness in the town's school, he meets his love interest, Alva (Rashida Jones), a teacher with no one to teach because Smeerensburg children don't go to school, as not to risk the children of both families becoming friends. So, Alva is stuck selling fish until she can get enough money to leave the island for good. As Alva, Jones has less to do than the rest of the cast, but provides a voice of guidance for Jesper.
Jesper makes his home in an abandoned and boarded-up post office that's now being used as a chicken coop. It's funny watching Jesper attempt to navigate an environment so far from the life of leisure, decadence, and silk sheets that he's used to. Schwartzman, most notably recognized by the HBO series Bored to Death and his collaborations with Wes Anderson, brings his signature charm to the character, reminding the audience of why he steals the show in everything he's in. Jesper spends much of the movie struggling to get the town interested in sending letters. But when he seems to have hit rock bottom, he discovers a woodsman's cabin on the other side of the island. This cabin is the home of many toys and their maker, an imposing giant of a man armed with an ax named Klaus (JK Simmons).