Tinie Tempah follows more brave homeowners as they build extraordinary extensions. In Warwickshire, he follows a couple taking on a million-pound retirement project of adding an underground swimming pool and spa extension to their curved mega-home. However, they face a battle with the property's curves and to somehow make it eco-friendly. On the lookout for inspiration, Tinie also visits two other super-luxe subterranean extensions devoted entirely to lives of leisure.
