A film about the breakdown men of the Seven Seas Narrated by FRANK WINDSOR A third of all vessels are involved in accidents every year. The thin red line that prevents the crippled ship from becoming a total loss is the Professional Salvor - the salvage man with his powerful ocean-going tug. His work is tough and skilled. It is also secretive and highly competitive. He is playing for high stakes - salvage awards in cash that can run into hundreds of thousands of pounds. So he lurks around the congested shipping lanes and maritime black spots ... waiting and listening. Sooner or later, the radio operator will pick up a ' May Day' call, and then the salvage man will pounce ... Written and produced by ROGER MILLS