One day, without warning, 50% of the human population became psychopaths. The world turned cold, and "love" became an undefined, alien language. In this era of emotional void, Sua lives as a professional fixer—a perfect "half-psychopath" whose emotional centers are completely paralyzed. Her only flaw in this perfect coldness is her younger sister, Jia. Jia has always been obsessively fixated on the color Red. While Sua simply believes it is her sister’s favorite color, the truth behind Jia’s obsession is heartbreaking: Jia desperately wanted to be the "beating heart" inside her sister's cold chest—a pulse for a woman who could no longer feel. When Jia is kidnapped by a villain driven by a twisted obsession with Sua, Sua infiltrates the enemy’s stronghold. She cannot feel love, but driven by a cold, honest lethal intent, she goes to reclaim what is hers. "I don’t know what 'I love you' means, but I’m taking my sister back." In the final moment, what gift will this psychopath sister—who has never been able to tell a lie—offer to her sister? 📌 Director’s Note Symbolism: The color Red, which permeates the film, symbolizes the "warmth of a heart" that Jia desperately wanted to give to Sua. Emotional Contrast: The film captures the tragic aesthetic born from the collision between Sua’s monochromatic, cold world and Jia’s vibrant, red obsession. The Weight of the Ending: For a psychopath, saying "I love you" is not just a confession; it is a sublime sacrifice—shattering one’s own worldview to finally enter the world of another.