MasterChef judge Gregg Wallace and mathematician Dr Hannah Fry take over a restaurant and invite five special guests to enjoy a dinner party with a difference, where they will be scored on the carbon footprint of every dish they choose. Food accounts for a third of all greenhouse gas emissions, so making informed choices about what we eat is more important than ever. Diners Sara Pascoe, Amol Rajan, Nikki Fox, Desiree Burch and Matthew Fort choose from a menu of tantalising treats, each of which tells its own environmental story. But will they be able to sort the eco-goodies from the eco-nasties hidden in each course? Gregg is with the kitchen team preparing delicious dishes and uncovering tips and tricks we can all use to cook more sustainably. Hannah is working with environmental scientists to reveal the carbon footprint of every single item on the menu and uncovering the latest research that can help us enjoy the food we love that doesn't cost the Earth.

Dr George McGavin and Dr Zoe Laughlin set up base camp at one of the UK's biggest sewage works to investigate the revolutionary science finding vital renewable resources and undiscovered life in human waste. Teaming up with world-class scientists, they search for biological entities in sewage with potentially lifesaving medical properties, find out how pee can generate electricity, how gas from poo can fuel a car and how nutrients in waste can help solve the soil crisis. They follow each stage of the sewage treatment process, revealing what the stuff we flush can tell us about how we live today, and the mindboggling biotechnology being harnessed to clean it, making the wastewater safe enough to return to the environment