When stars are born, hundreds of thousands can form in one cluster. Amongst these are massive stars which, though short-lived, have far-reaching effects on the evolution of the entire galaxy. Thomas Haworth shares the latest understandings of how the energy from massive stars is impacting the clusters and galaxies around them. From the destruction of planet-forming discs to energy surges from supernovae, the lives of massive stars have far-reaching consequences for their surroundings.