LISA MILLER, a fifteen-year-old radical gender activist, lives in a quiet, middle-class European suburb. Convinced that the traditional nuclear family is the root of all evil, she makes a crossed­ out photo of her own family the centerpiece of her campaign.

Her conventional mum, REBECCA (45), dismisses Lisa’s activism as a phase, chalking it up to typical teenage angst and attention-seeking jealousy of her neurodiverse brother, NOAH (10). Lisa’s dad, MAX ( 45) and Noah hide behind their devices to avoid the mother-daughter feud. At school, Lisa is seen as a weird nuisance, alienating and irritating everyone with her eccentric campaigns.

Then the unthinkable happens: women worldwide suddenly lose all interest in men and turn instead to other women. Men, feeling rejected, scramble to explain the mysterious „Switch“ as a virus while women readily embrace the new reality.

Suddenly Lisa’s weird ideas become popular. Her movement skyrockets beyond her wildest dreams, turning Lisa into a „Switch“ icon. Even Rebecca, who falls for young receptionist TINA (22), wants Lisa’s advice. Feeling relevant to her mum for the first time in years, Lisa encourages her to follow her heart but is taken aback when Rebecca immediately moves out.

Heartbroken, Max embarks on a path of self-improvement, resorting to astrology and plastic surgery in ever-increasing desperation to win Rebecca back. Noah, naively convinced his coding caused the Switch, becomes obsessed with attempting to reverse it, refusing to eat or sleep.

As society becomes increasingly polarised and gender-segregated, Lisa falls in love with Charlie, the most conventionally attractive boy in school. She’s faced with the ultimate irony – she hasn’t Switched. Disappointed with herself, after much internal struggle she finally „comes out“ to her followers, but her confession makes her a pariah and she’s ejected from her own movement – an outcast again. Her totally Switched mum dismisses Lisa’s claim not to have experienced the change as yet another contrarian, attention-seeking ploy, reigniting their feud with greater intensity.

The world is in chaos – men and women can’t find common ground on even the simplest issues. After a string of failed negotiations between now-divided male and female governments, a drastic decision is made: to split into separate republics, with a third autonomous LGBTQ zone, dividing property and children between them.

Lisa, furious at being stuck in the female republic with her mum and Tina, secretly plans a protest against the gender apartheid. With Max’s help, she meets Charlie at the border and their „intimate protest“ leads to her arrest. Meanwhile, Noah deteriorates and, to Lisa’s horror, is hospitalized.

When a child is shot trying to climb the border fence to see his dad, tensions explode, with both sides blaming each other. The police believe that rebellious Lisa will be safer locked up, and she’s incarcerated in the same hospital as Noah. As the male and female republics inch towards war, Max and Rebecca join opposing crowds marching to the dividing border fence. Lisa’s few remaining friends arrange Lisa’s escape so they can protest while the police are distracted – but it means leaving catatonic Noah behind.

Finally prioritizing her family over her ideology, Lisa chooses to stay with Noah. Suddenly, snow begins to fall. As the snow lands on the raging female and male crowds, their anger cools.

Confused and disoriented, everyone stops. Max spots Rebecca through the fence; their eyes meet.

Noah wakes up and asks for food.