The Second Doctor, Ben and Polly land on what appears to be an idyllic world. So peaceful does it seem that Polly immediately dubs it "Heaven". After some exploration, Ben discovers the world is inhabited. The TARDIS crew go to meet the locals, humanoids dressed in what resemble Greek clothing. They speak musically and stop the Doctor and his companions from bickering with each other. This world, it turns out, is actually named "Harmony", and they wish to ensure the name is accurate.