Set in a devastated December 2021, Resiklo depicts a world where Earth has been conquered by an insectoid alien race known as the Balangs. The human population has been decimated, with many survivors transformed into Mutanos—mutated, mindless slaves serving their alien overlords. In the Philippines, the remnants of society have retreated to a hidden, walled community called Paraiso, where they live in a state of constant vigilance and extreme resource depletion.

The film’s central dynamic is a "Third World" approach to science fiction, where the future is not defined by sleek high-tech advancements but by guerrilla engineering and upcycling. Because the global supply chain and industrial base have vanished, humanity's primary survival strategy is the literal recycling of 20th-century waste. This manifests in the creation of giant mecha pilots and armored vehicles constructed entirely from junked cars, tractors, and industrial scrap. It presents a vision of 2021 where the ecological and economic failures of the past force a return to fundamental mechanical ingenuity.

Compared to the actual 2021, the film’s predictions of total environmental collapse and alien occupation proved to be purely metaphorical, though its themes of resource scarcity and the necessity of sustainable technology remain culturally relevant. While the film accurately sensed a growing global anxiety regarding waste management and environmental destruction, its depiction of 2021 as a landscape of mecha-battles and cyborg slaves diverged significantly from reality. Instead of fighting alien locusts, the actual 2021 was defined by a global biological crisis and digital isolation, though the film’s focus on walled communities and sanctuaries mirrors the fragmented nature of modern urban security and pandemic-era borders.