After a deadly heatwave in Karachi, Pakistan, the use of air conditioning is on the rise – for those who can afford it. Raza, a young repairman, has never been busier. But energy-hungry Aircon itself helps drive climate change. Meanwhile, entrepreneur Shahzad Qureshi is trying to cool the city by creating urban forests. With 2021 set to be one of the hottest years on Earth, Life at 50°C presents the human impact of climate change.