 Striking suddenly, a killer wave of water struck the counties of the Bristol Channel on 30 January 1607. The flooding stretched as far as the Glastonbury Tor 14 miles inland, and inundated two hundred square miles of Somerset, Devon, Glamorganshire and Monmouthshire.  Timewatch  follows the research of two scientists, Professor Simon Haslett from Bath Spa University and Australian geologist Ted Bryant from the University of Wollongong, who are increasingly convinced that the killer wave was not simply a freak storm but a rare British tsunami.