Set over a sweltering A-Level results day in London, Last Swim follows Ziba, a promising British-Iranian teen, as she leads her friends on an eventful journey across the city, culminating in a once in a lifetime astronomical event. Despite the celebratory atmosphere, Ziba struggles to retain her characteristic optimism as she finds herself battling the intrusive fears and secrets she’s been hiding from her friends. As day turns to night, Ziba has no choice but to confront the irreversible event she has planned for the end of this last day of untainted adolescence.