TROPIC (TROPIQUE) is a film that mixes genres to talk about humanity and what it means to accept or abandon what cannot be changed. Although some structural issues weigh it down, the film’s allusions to sci-fi horror elevate this story, mainly told through unspoken expressions and gestures.

Tristán (Louis Peres) and Lázaro (Pablo Cobo) are twin brothers, competing against other young candidates for France’s place on Europe’s first space colonisation mission. Their lives are completely intertwined, from their shared home with their mother (Marta Nieto) to the gruelling battery of underwater breathing tests, physical exercise, and philosophy classes required by their astronaut training.

Tristán is the clear favourite for astronaut selection until a cosmic event strikes the pond where he and his brother are swimming. Lázaro escapes unaffected, but Tristán’s left half – including his brain – is altered and disfigured by the mysterious liquid invading the water. There’s no way he can continue in the astronaut training, and Lázaro has to push himself to take his brother’s place and come to terms with the person his brother is now.

TROPIC is careful in how it alludes to sci-fi horror touchstones. There’s a clear alignment with John Carpenter’s sci-fi horrors, particularly THE THING (TROPIC’s original working title was THING BEHIND THE STARS). The opening credits have a very 1980s-style font and pounding synth score, which situate the film in an ‘80s tradition of pulp sci-fi without being too overt. However, the film balances this with its slowness and meditative shows of tranquil forest wilderness that are more reminiscent of Apichatpong Weerasethakul’s MEMORIA. Like MEMORIA, the film’s sci-fi elements creep in slowly and never overwhelm the tender narrative at the heart of it.

As it becomes clear that Tristán has not only changed but is practically a different person now, Lázaro must confront what to do when the person who drives you is irrevocably changed. Tristán is not just physically and mentally disabled but terrified of the water he once thrived in and quiet where he was once confident. His friends are now the disabled kids in the school conveniently next door to the astronaut training school. Lazáro struggles with accepting or abandoning his brother while grappling with the broader idea that space colonisation is itself abandoning Earth to a vaguely implied but all too familiar climate crisis. If he succeeds in qualifying for the mission, he’ll abandon his brother and the whole planet.

Although the film is by its nature slow and contemplative, some aspects could benefit from tighter editing or more focus. A rivalry with fellow candidate Louis (Marvin Dubart) feels underdeveloped through the first half, so it feels contrived when he plays a pivotal role in an emotionally unnecessary dramatic climax towards the film’s end. TROPIC’s focus is squarely on the relationship between the two brothers, so other relationships feel ancillary in a way that undermines some of the film’s wider themes.