Butterfly is a character-driven spy thriller that explores advanced household dynamics throughout the treacherous world of worldwide espionage. It is centered on David Jung (Kim), an enigmatic, extremely unpredictable former US intelligence operative residing in South Korea, whose life is blown to items when the results of an unattainable determination from his previous come again to hang-out him, and he finds himself pursued by Rebecca (Hardesty), a lethal, sociopathic younger agent assigned to kill him, and Caddis, the sinister spy group she works for.