Britain was shocked when it woke to news of the Grenfell Tower fire. For the film crew who had been following a group of the capital’s firefighters over the last year, the heroism on display that night wasn’t a surprise as this three-part series dramatically shows.

In this first episode, brigades tackle floods and a burning bus, yet the most moving scenes are those in which the firefighters who were at Grenfell Tower last month talk about their experiences that fateful night.