Scallop divers are our eye witnesses - able to tell us what goes on beneath the waves. Alasdair Hughson, M.D. of Keltic Seafare and chairman of the Scottish Creel Fishermen's Federation is also a scallop diver. He has dived Scotland's seas for 32 years and has seen the changes caused by dredging first hand. He shares a short extract of a letter he felt compelled to write to those in charge of the fisheries after witnessing the impact of dredgers in a particularly bad week. Using footage from within Wester Ross Marine Protected Area ( taken during Subseatv-SCFF-Seachange surveys) the film shows how damage takes years to recover but also what the remnants of intact ecosystems look like too.