If a penny falls off the top of the Empire State Building and hits someone on the pavement, will it kill them? Science geek and adrenaline junkie Greg Foot lives to risk his neck and get to the bottom of such things. Greg comes under sustained attack - he's immersed in cold water to discover what extreme temperature can do to you and has his fingers hammered to test a weird painkiller. And then he investigates spontaneous human combustion. Curiouser and curiouser...