Massive Attack is set to perform their first hometown show in five years at Clifton Downs, Bristol, on August 25, aiming to establish a new standard for climate action in the music industry. The event, titled 'Act 1.5', is designed to be the lowest-carbon concert of its scale, with all food being vegan, compostable toilets, and energy supplied entirely by renewable sources. Approximately 34,000 attendees are encouraged to use sustainable transport options, including special trains, to minimize environmental impact. Band members Robert '3D' Del Naja and Grant 'Daddy G' Marshall emphasize the importance of acting on climate change rather than merely discussing it, stating that the show should feel like a normal gig despite its eco-friendly practices. The concert is seen as a potential turning point for Bristol's music scene and aims to inspire future artists while providing a template for the entire live music industry.